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Understanding the electronics related to restricted performance
On Christmas holiday we took a long road trip and after three hours in rising elevation the Restricted Performance (amber) came on. I took it to a reputable independent in Taupo who put the OBD reader on it and found the MAF sensor was gunked with carbon. It got better, but there still must be other sensors that are problematic because the message came on a few times afterwards - once driving up a steep mountain road to the top of Ruapehu and after that shortly after we would get underway.
The indy mechanic said he learned his trade before electronics, but when OBD came in he realised he had to learn it or find another career. He explained that once one works at it, it's not that difficult and it provides a lot of diagnostics. However, it's not as clear as it could be - pointing to problems rather than being clear what needs to be cleaned or replaced. Also there is the additional problem when the mechanicals are OK, but the sensor (or the OBD itself) fail, as happened with my MAF.
Now that the X350 line is approaching the bottom of its value curve where depreciation is exhausted and it shifts to becoming a classic collectible worthy of restoration, it will be helpful for the DIY owner to understand exactly how many sensors feed the OBD, what they do, where they are and which ones tend to need attention or replacement due to age and/or miles. This information probably is available to Jaguar dealers, but unfortunately (a) they charge prices not aligned with car value and (b) after 20 years they really are not interested, and the law does not compel them to be interested. Accordingly, the owner must become more familiar, like the indy mechanic, and also be able to do a certain amount of field checking without necessarily having a good OBD reader when problems crop up.
Questions:
Please list all sensors that connect to the OBD, directly or indirectly and show a photo, drawing and description of where they are located.
Indicate ones that are affected by age, miles, humidity, heat, cold, etc, and what happens when they give off the wrong data (and why they do, like the carbon buildup on my MAF)
Describe the symptoms they throw off (like amber restricted performance) and what side-effects (like screwing up shifting)
List the common error codes an OBD reader would show
If one were to do a classic restoration, where one replaces all known weaknesses regardless of actual performance, what would the list related to OBD and sensors contain?
I expect this will be a piecemeal list as members contribute their own experience, but if there is a very knowledgeable person out there, it would be great to get a comprehensive answer where the moderator may choose to make it a sticky.
To start off, in the next post, I will include a web site I found using google
I commend your noble and ambitious initiative! To compile an exhaustive database that answers all of your questions would fill tens of thousands of pages.
The "Restricted Performance" warning on the Instrument Cluster is a catchall for many possible malfunctions that cause the Engine Control Module, Transmission Control Module or Anti-Lock Brake Module to impose default settings to protect the vehicle from further damage. The list of possible causes is very long.
The good news is that many of the answers are already available from existing references such as the ones listed below.
1. The Diagnostic Trouble Code (DTC) Summaries manual, an extended version of which can be downloaded at the link below. You won't find the term "Restricted Performance" in the manual, but you can use the Adobe Acrobat Reader search function (Ctrl+F or Cmd+F) to search "Limp Home," "Limp Home Mode," "Restricted," "Limited," "Inhibited," etc. to find faults that cause control modules to enter protective default modes. You'll find that some Limp Modes are Mechanical, and some are Electronic. See the Default Action for each DTC. These are the official Jaguar definitions and possible causes of each code, which often differ from generic OBDII definitions such as those listed in post #4 (many of which are not implemented on the Jaguar X350).
2. The Jaguar Factory Workshop Manual, available from this forum's download area in six sections at these links. The FWM provides pinpoint tests for diagnosing the cause of many DTCs.
3. Jaguar Engine Management System Training Manuals such as the ones at the links below. These describe all of the sensors, their functions, and how the ECM uses the signals from each sensor:
5. Technical Service Bulletins These contain knowledge gained after the initial service documentation was published and vehicles entered production and use and pattern failures emerged. Many X350 TSBs are available in the download area of this forum and at our member Gus' website, jagrepair.com
6. DIY Owner Accounts available in this forum, which frequently report resolutions to malfunctions that are not listed among the "Possible Causes" listed in the DTC Summaries or Workshop Manual. Many of our members are intelligent, talented, experienced DIY diagnosticians and mechanics who are passionate about Jaguars and often find solutions to malfunctions that even Jaguar dealers don't know about. These accounts already fill tens of thousands of threads at the Jaguar Forums, where they are, to a great degree, organized by topic and easily searchable with google or the forum's Advanced Search function.
Diagnostics for the DIY Owner Attempting to diagnose any modern vehicle without an appropriate scan tool is a virtual guarantee of wasted time and money. Fortunately, for around USD $20.00 you can acquire an ELM327 bluetooth (Android) or WiFi (iPhone) OBDII adapter and the Torque Pro app (Android) or DashCommand app (iPhone) and read and clear Powertrain (P-prefix) DTCs, and view Live Data and Mode $06 data. For $80.00 to $200.00, the iCarsoft dedicated Jaguar Land Rover scan tools receive good reviews from our members. For $160.00 to $400.00, the Foxwell dedicated Jaguar Land Rover scan tools are also well-reviewed by our members.
For serious diagnostics, a bi-directional scan tool that can read the proprietary Jaguar Powertrain (P-), Chassis (C-), Body (B-) and Network (U-) DTCs is not a luxury but a necessity. These include the Jaguar Land Rover IDS/SDD systems used by the dealership service departments, high-end laptop-based systems like AutoEnginuity and AutoLogic with the Jaguar enhancements, and high-end scan tools from Autel, Launch, SnapOn, etc.
One thing to keep in mind is that Diagnostic Trouble Codes do not necessarily mean that a specific component has failed, but rather that something in a system has failed or is not performing properly. That could be a wiring fault, corrosion on electrical connectors or ground points, a power supply issue,etc. What DTCs do is help narrow down the diagnosis, but actual diagnosis by the technician is still required. Owners who throw new parts at DTCs without fully diagnosing the cause quickly learn that it can get very expensive and not resolve the true underlying issue.
I hope the documents linked above will answer many of your questions and form a solid foundation as you continue your X350 journey, and thanks for sharing the information you've been gathering as well!
With the Restricted Performance error message, the car is indicating that the engine management system has gone into a “limp” mode to protect certain systems and components. This changes depending on the system or components being protected.
For example, if a coil pack (or packs) is failing, unburnt fuel would be getting into the exhaust system, which would damage the catalytic converters. So to protect the catalytic converters, fueling on the affected cylinder(s) is switched off. This is why the car appears to run very badly if this is happening.
Our research found that it occurs more in S-Type and XJ-Series Jaguars.
What are the symptoms of Restricted Performance?
Generally, the Restricted Performance light either comes on before and during a cold start or while driving. If the error message illuminates while driving, you can experience limited acceleration of 1800 – 2000 RPM. Many times, the message displays when going heavy (around three-quarters down) on the accelerator. The car is trying to protect itself when this happens.
What are the possible causes?
First and foremost, always use an OBD scanner to run diagnostics when you get the Restricted Performance message. If you’re a “do-it-yourselfer” but don’t own a scanner, you can go to any local auto parts supply store and use theirs. If you prefer to take the car into a Jaguar specialized mechanic, they have a diagnostic scanner. Using a scanner is very important in pointing you toward a smaller list of the source that is causing the problem. A Jaguar mechanic will have the certification and experience to diagnose accurately the performance issue, and repair to OEM specifications.
Common Restricted Performance Message Problems
The Restricted Performance message generally indicates issues with these systems in your car:
air intake and/or throttle body
fuel system
Possible causes for the Restricted Performance error can be from leaks in airflow, mass airflow (MAF) issues, fuel, intercooler hoses, throttle body housing, and gaps in hose closures.
More specifically, these are some of the most common causes of the error (including diagnostic codes where possible):
Gearbox fault – Can cause hard shifts in S-Types (2002 – 2008)
Breather hose connected to the throttle body
EGR valve not working – diagnostics read “air mass and turbo”
Turbo Turbine Inlet Valve Stuck Open (P22D2)
Turbo Turbine Inlet Valve Control Circuit – Open (P22CF)
Faulty turbo actuator
Split intercooler
Inlet air leak or leaking hose
Check for these issues when diagnosing your Jaguar
If you are working on the car yourself, run through this check list:
Check the obvious things like the air intake box (air filter housing) for cracks or to make sure all of the clasps are fastened/not missing.
Check the breather hose from the engine that intersects the intake pipe to make sure it isn’t cracked and that both ends are completely fastened.
Check the mass airflow (MAF) sensor right after the air intake box to make sure the wiring harness is completely fastened and remove it and apply a small amount of cleaner if dirty.
Check the air intake pipe for cracks and where it connects with the throttle body and make sure that seal is tight.
Check the o-ring seals around the dipstick and the breather hoses between the engine and the firewall and the plastic air intake manifold seals.
If your car won’t start, it’s possible you have a clog in the fuel lines or a fuel pump problem.
Check (because we found other folks with the error also had experienced) faulty dipstick o-ring, faulty mass airflow sensor, a cracked breather hose, and a cracked plastic nozzle that extends from the valve cover.
Hi x350,
I know your car is normally aspirated, but my car (Super V8) came with a regular RP (restricted performance) scenario. After clearing the fault codes it would be fine until a bit of the performance was used. Then, a supercharger coolant pump error (a P2601 I think) would occur, then there would be the yellow warning light and the RP on the message centre.
The previous owner had tried a number of fixes, none of which were successful. I replaced the supercharger coolant pump, but that didn't fix it. After some investigation, I found that one of the invisible PCB relays in the front power distribution box (engine fuse box) was faulty. I connected an external relay to jumper around it and it has behaved itself since then. This was an adaption of a fix on this forum by another member who had the other half of the same relay fail, affecting the heaters in the oxygen sensors in the catalysts.
I have just taken the fuse box out, stripped it down, separated the two printed circuits by cutting the 125 pins joining them, replaced the faulty relay, and refitted the boards together. I will find out tomorrow if my repair is successful.
With these engines, the supercharger coolant pump runs all the time the ignition is on, so if you listen closely by the right hand headlights, you can hear the pump running.
The rationale behind the RP is that without sufficient cooling provided by the pump, the intake charge temperature could rise to the point where detonation and engine damage might occur.
Below is another Jag dealer offering useful information. What we now need to do though is look beyond the Fault codes to understand how they all work together. There are three options:
Something is really wrong - the transmission is dying, the brakes are failing, the engine is wearing out, the catalytic converter is fouled etc.
A sensor or a wiring connection is failing and the computer is confused
The OBD computer is failing (common problem with Mercedes during the Chrysler years... soldering joints get hairline cracks)
Perhaps we need to expand the common causes in Jags.
Loose Gas Cap: Your gas cap is loose, broken, or simply missing. Gas cap issues can reduce fuel pressure and allow fuel vapors to escape, reducing fuel economy and increasing harmful emissions.
Failing Catalytic Converter: Your catalytic converter can eventually clog with material, especially with higher mileage vehicles. The catalytic converter is a vital part of the emissions system, removing toxic carbon monoxide. A failing or clogged catalytic converter can severely impact fuel economy and vehicle performance.
Fouled Spark Plugs or Spark Plug Wires: Over time you will eventually need new spark plugs or spark plug wires. Your spark plugs create a hot spark that ignites the air-and-fuel mixture in the cylinder, allowing your engine start and run. Faulty spark plugs or spark plug wires can cause your engine to misfire, reducing fuel economy, performance, and even prevent it from running altogether.
Faulty Oxygen Sensor: Due to long exposure to hot exhaust gas, your oxygen sensor might need replacing. The oxygen sensor provides vital air-fuel mixture information to the ECU. A faulty oxygen sensor can cause your vehicle's computer to supply the engine with too much or too little fuel. An engine with too little fuel is at risk of total engine failure, and an engine with too much fuel will create excessive smoke and odor.
Faulty Mass Air Flow Sensor: When exposed to dirty or particle-rich air, the Mass Air Flow (MAF) sensor could fail. Like the oxygen sensors, the MAF sensor measures the amount of air entering the engine and help ensure the proper air-fuel mixture. A faulty MAF sensor can cause your engine to misfire, ultimately causing poor fuel economy, performance, and potentially more unnecessary damage to your engine.
P0011 - Camshaft variable timing solenoid failure, Engine oil level is too low, The engine is not timed correctly, The engine oil does not meet the manufacturer's requirements, Variable valve timing actuator failure, Worn timing chain
P0012 Camshaft variable timing solenoid failure, Engine oil level is too low, The engine is not timed correctly, The engine oil does not meet the manufacturer's requirements, Variable valve timing actuator failure, Worn timing chain
P0014 Camshaft variable timing solenoid failure, Engine oil level is too low, The engine is not timed correctly, The engine oil does not meet the manufacturer's requirements, Variable valve timing actuator failure, Worn timing chain
P0101:Large vacuum leaks, Split Intake Air Boot or PCV Hose, Defective intake manifold gaskets, Mass Airflow Sensor (MAF), Mass Air Flow Sensor circuit and or wiring problems, Defective Barometric Pressure Sensor, Dirty or contaminated Mass Air Flow Sensing wire or filament, PCM software needs to be updated
P0102 The Mass Airflow Sensor (MAF) Sensor is unplugged or the wiring is damaged, Loose or corroded electrical terminals in the MAF Sensor circuit, Faulty MAF Sensor
P0113 Defective Intake Air Temperature Sensor, Dirty air filter, Defective Mass Air Flow Sensor, Faulty or corroded Intake Air Temperature Sensor wiring or connections
P0128 Defective Engine Thermostat, Defective Engine Coolant Temperature Sensor, Defective Intake Air Temperature Sensor, Defective Cooling System, Low Engine Coolant, Dirty Engine Coolant causing incorrect Coolant Temperature Sensor readings, Defective/always running Engine Cooling fan(s)
P0135 Defective Oxygen Sensor/Air Fuel Ratio Sensor, defective Oxygen Sensor/Air Fuel Ratio Sensor Heater Circuit, Exhaust System Leak, Intake Air System leak, Low Fuel Pressure, Defective Engine Coolant Temperature Sensor, Defective sensor wiring and/or circuit problem, PCM software needs to be updated, Defective PCM
P0171 Control module software needs to be updated, Vacuum leaks (intake manifold gaskets, vacuum hoses, PCV hoses, etc.), Mass air flow sensor, Plugged fuel filter or weak fuel pump, Plugged or dirty fuel injectors
P0174 PCM software needs to be updated, Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.), Faulty Mass Airflow (MAF) Sensor, Plugged Fuel Filter or weak Fuel Pump, Plugged or dirty Fuel Injectors
P0200 Defective Fuel Injector, Faulty or corroded Fuel Injector, wiring, and/or connections, Plugged Fuel Injector, Dirt in the Fuel Injector
P0201 Defective Fuel Injector, Faulty or corroded Fuel Injector, wiring, and/or connections, Plugged Fuel Injector, Dirt in the Fuel Injector
P0202 Malfunction of the Fuel Injector, Malfunction of the PCM Fuel Injector driver circuit, Defective wiring/connections in the Fuel Injector wiring harness, Defective Fuel Injector power circuit(s)
P0300 Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR system, Defective Mass Air Flow Sensor, Defective Crankshaft and/or Camshaft Sensor, Defective Throttle Position Sensor, Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems)
P0301 Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR system, Defective Mass Air Flow Sensor, Defective Crankshaft and/or Camshaft Sensor, Defective Throttle Position Sensor, Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems)
P0302 Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR system, Defective Mass Air Flow Sensor, Defective Crankshaft and/or Camshaft Sensor, Defective Throttle Position Sensor, Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems)
P0303 Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR system, Defective Mass Air Flow Sensor, Defective Crankshaft and/or Camshaft Sensor, Defective Throttle Position Sensor, Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems)
P0304 Worn out spark plugs, ignition wires, coil(s), distributor cap and rotor (when applicable), Incorrect ignition timing, Vacuum leak(s), Low or weak fuel pressure, Improperly functioning EGR system, Defective Mass Air Flow Sensor, Defective Crankshaft and/or Camshaft Sensor, Defective Throttle Position Sensor, Mechanical engine problems (i.e.—low compression, leaking head gasket(s), or valve problems)
P0401 Restriction in the EGR passages, usually caused by carbon buildup, The EGR Valve is defective, Lack of proper vacuum or electrical signal to the EGR valve, Malfunctioning EGR Vacuum supply solenoid, Lack of proper EGR system feedback to the computer from the: Manifold Absolute Pressure Sensor (MAP), Differential EGR Pressure Feedback Sensor (DPFE), EGR Valve Position Sensor (EVP), EGR Temperature Sensor
P0420 Inefficient Catalytic Converter(s), Defective Front or Rear Oxygen Sensor(s), Misfiring engines
P0430 Defective Catalytic Converter, Internal engine damage resulting in high oil consumption and/or a leaking Head Gasket has damaged the Catalytic Converter
P0440 Missing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and/or Evaporative Purge Valve, Defective or damaged fuel tank
P0441 Missing fuel cap, Stuck open or closed purge valve, Defective or damaged fuel cap, Distorted, damaged or cracked Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve, Defective or damaged fuel tank
P0442 Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Small tear or puncture in the Evaporative system hose(s) and/or Carbon Canister, Defective Fuel Tank Sending Unit gasket or seal, Small split in a seam of the Carbon Canister, Defective Evaporative Vent Valve and/or Evaporative Purge Valve, Defective or damaged Fuel Tank, Defective Fuel Tank Pressure Sensor, Defective Leak Detection Pump, Slightly loose and/or worn clamps or hardened O-rings anywhere in the EVAP system
P0455 Missing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and/or Evaporative Purge Valve, Defective or damaged fuel tank, Defective Fuel Tank Pressure Sensor
P0500 Defective Vehicle Speed Sensor, Defective Speedometer, Vehicle Speed Sensor wiring or connector, Communication (CAN) bus problems, Defective transmission or differential Vehicle Speed Sensor drive gear
P0501 Defective Vehicle Speed Sensor, Defective Speedometer, Vehicle Speed Sensor wiring or connector, Communication (CAN) bus problems, Defective transmission or differential Vehicle Speed Sensor drive gear
P0505 Defective Idle Air Control Motor, Intake Manifold Vacuum leaks, Carbon buildup in the Throttle Body air passages
P0506 Defective/sticking Idle Air Control Motor, Intake Manifold Vacuum leaks, Carbon buildup in the Throttle Body air passages, Defective Power Steering Pressure Switch
P0507 Defective/sticking Idle Air Control Motor, Intake Manifold Vacuum leaks, Carbon buildup in the Throttle Body air passages, Defective Coolant Temperature Sensor, Defective Charging System/Alternator, Defective Power Steering Pressure Switch
P0600 Defective PCM (Power Train Control Module), Defective PCM data bus wiring/connections, Defective PCM data bus ground circuit(s), Defective PCM or other control module controlled output devices, Defective CAN bus communication
P0601 Lack of proper voltage to the PCM, Defective PCM memory module, Defective PCM ground circuit(s), Defective PCM controlled output devices
P0602 Powertrain Control Module (PCM) failure, Wiring issue
P0603 Lack of proper voltage to the Keep Alive Memory connection on the PCM, Defective PCM Keep Alive Memory Module (KAM), Defective PCM ground circuit(s), Defective PCM controlled output devices
P0605 Lack of proper voltage and/or ground to the PCM, Defective PCM ROM memory module, Defective PCM ground circuit(s), Defective PCM controlled output devices
P0700 Defective Shift Solenoids, Defective Engine Coolant Temperature Sensor, Defective Valve Body, Dirty transmission fluid that restricts the hydraulic passages
P0705 Defective Transmission Range Sensor (PRNDL input), Defective Transmission Range Sensor (PRNDL input) wiring or connector, Defective Valve Body, Defective manual shift valve linkage, Dirty transmission fluid that restricts the hydraulic passages
P0706 Defective Transmission Range Sensor (PRNDL input), Defective Transmission Range Sensor (PRNDL input) wiring or connector, Defective Valve Body, Defective manual shift valve linkage, Dirty transmission fluid that restricts the hydraulic passages
P0720 Defective Output Speed Sensor, Defective Shift Solenoids, Defective Engine Coolant Temperature Sensor, Defective Valve Body, Dirty transmission fluid that restricts the hydraulic passages, Defective Output Speed Sensor wiring or connector
P0730 Defective Shift Solenoids, Defective Engine Coolant Temperature Sensor, Defective Valve Body, Dirty transmission fluid that restricts the hydraulic passages
P0841 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission fluid pressure sensor failure, Wiring issue
P0842 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission fluid pressure sensor failure, Wiring issue
P0845 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission fluid pressure sensor failure, Wiring issue
P0846 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission fluid pressure sensor failure, Wiring issue
P0847 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission fluid pressure sensor failure, Wiring issue
P0A0D High voltage safety device failure, Inverter/converter assembly failure, Power management control module failure, Service disconnect plug is not properly connected, Wiring issue
P0A0F Hybrid transaxle assembly failure, Internal engine failure, Power management control module failure
P0A7F Poor connections at the HV battery, A problem with the HV battery, ECU issues
P0A80 High voltage battery assembly failure
P0B22 Battery contactor assembly failure, Battery Energy Control Module (BECM) failure
P0B24 Battery Energy Control Module (BECM) failure, High voltage battery assembly failure, Wiring issue
P0B26 Battery Energy Control Module (BECM) failure, High voltage battery assembly failure, Wiring issue
P0B28 Battery Energy Control Module (BECM) failure, High voltage battery assembly failure, Wiring issue
P0B30 Battery Energy Control Module (BECM) failure, High voltage battery assembly failure, Wiring issue
P0C00 Drive motor generator power inverter control module failure
P0C09 Drive motor generator assembly failure, Drive motor generator power inverter control module failure
P0C11 Coolant system leak, Drive motor generator power inverter control module failure, Engine cooling fan failure, Water pump failure
P0C14 Coolant system leak, Drive motor generator power inverter control module failure, Engine cooling fan failure, Water pump failure
P0C15 Coolant system leak, Drive motor generator power inverter control module failure, Engine cooling fan failure, Water pump failure
P2000 Diesel Particulate Filter (DPF) failure, Intake air leak, Mass Airflow (MAF) sensor is dirty/loss of calibration
PP2002 Diesel Particulate Filter (DPF) failure, Intake air leak, Mass Airflow (MAF) sensor is dirty/loss of calibration
P2004 A failed IMRC actuator, A problem with the intake manifold or linkage, Wiring issues
P2006 Intake manifold runner control actuator failure, Powertrain Control Module (PCM) failure, Restricted vacuum lines
P2101 Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle control motor failure, Wiring issue
P2122 Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle control motor failure, Wiring issue
P2135 Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle Position Sensor (TPS) failure, Wiring issue
P2138 Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle Position Sensor (TPS) failure, Wiring issue
P2181 Engine coolant heater failure, Engine coolant level is too low, Thermostat failure
P2601 Coolant Heat Storage (CHS) water pump failure, Coolant Heat Storage (CHS) water pump relay, Powertrain Control Module (PCM) failure, Wiring issue
P2607 Intake air heater, Powertrain Control Module (PCM) failure, Wiring issue
P2609 Intake air heater, Powertrain Control Module (PCM) failure, Wiring issue
P2610 An internal PCM problem, A problem with the PCM power or ground circuit
P2614 Broken tone ring, Camshaft Position Sensor (CMP) failure, Powertrain Control Module (PCM) failure, Wiring issue
P2706 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission shift solenoid failure, Wiring issue
P2711 Internal transmission failure, Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission solenoid failure, Wiring issue
P2714 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission shift solenoid failure, Wiring issue
P2716 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission shift solenoid failure, Wiring issue
P2723 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission shift solenoid failure, Wiring issue
P2803 Powertrain Control Module (PCM) failure, Transmission Control Module (TCM) failure, Transmission range sensor failure, Wiring issue
P2806 Powertrain Control Module (PCM) failure, Transmission Control Module (TCM) failure, Transmission range sensor failure, Transmission range sensor is out of adjustment, Wiring issue
P2809 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission pressure control solenoid failure, Wiring issue
P2810 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission pressure control solenoid failure, Wiring issue
P2815 Transmission Control Module (TCM) failure, Transmission fluid level is low, Transmission pressure control solenoid failure, Wiring issue
P2BA8 Faulty NOx Sensors, NOx Sensors harness is open or shorted, NOx Sensors circuit poor electrical connection, Fualty Diesel Particulate Filter (DPF)
P3000 Fuel level is too low, High voltage battery assembly failure, High voltage battery is not sufficiently charged
P3100 High voltage powertrain control module failure
P3400 Faulty Cylinder Deactivation System/td>
P3401 Engine oil level is too low, Powertrain Control Module (PCM) failure, Variable valve timing solenoid failure, Wiring issue
B0081 Wiring issues, Control module problems, A problem with the airbag
C0040 A faulty wheel speed sensor, A problem with the wheel speed sensor circuit, Reluctor issues, A problem with the ABS module
U0001 A faulty wheel speed sensor, A problem with the wheel speed sensor circuit, Reluctor issues, A problem with the ABS module
U0073 A faulty control module, A problem with the CAN bus
U0100 A faulty PCM, A problem with the control module circuit, A problem with the CAN bus
U0107 A dead battery, A faulty TAC module, A problem with TAC module circuit, A problem with the CAN bus
U0121 A dead battery, A faulty ABS module, A problem with ABS module circuit, A problem with the CAN bus
To help you better understand what you should do next, we've outlined possible scenarios:
(Note: this advice below is written for customers of a Jaguar dealer... for DIY, it means
(1) keep going carefully
(2) Something needs to be fixed now, don't put it off
(3) Stop. Be very careful, consider towing it home if the usual field tricks don't work (like turning off and on, opening and closing bonnet [don't know why that one works, but someone mentioned it], check battery cables, etc.)
(4) Stop, tow it home.
The check engine light only comes on in certain conditions: If the check engine light is coming on intermittently, be sure to notice any changes in the performance of your vehicle when the light is on. If you do notice a difference, try driving your vehicle as little as possible until you can bring it in for service. Most likely something is on the verge of failing and you run this risk of your vehicle not starting again.
The check engine light is constantly on: Your vehicle's onboard diagnostic system has determined something is wrong and needs to be fixed. Although your vehicle may seem to be operating fine, it's best to bring it in for service as soon as possible to prevent additional issues.
The check engine light is on and there is a noticeable performance issue: If you are noticing a consistent decrease in performance with the check engine light on, your vehicle may have automatically entered a "limp-mode" to prevent additional damage. In this case, you should come straight to our service center or have the vehicle towed to prevent any damage to the engine..
The check engine light is blinking while driving: Not to be confused with the light occasionally flickering in the first situation, if your check engine light is blinking consistently that typically indicates there is a major issue with your vehicle and you should pull over when safe. If you are not close to our service center, we suggest having your vehicle towed here just to be safe.
Hi x350,
I know your car is normally aspirated, but my car (Super V8) came with a regular RP (restricted performance) scenario. After clearing the fault codes it would be fine until a bit of the performance was used. Then, a supercharger coolant pump error (a P2601 I think) would occur, then there would be the yellow warning light and the RP on the message centre.
The previous owner had tried a number of fixes, none of which were successful. I replaced the supercharger coolant pump, but that didn't fix it. After some investigation, I found that one of the invisible PCB relays in the front power distribution box (engine fuse box) was faulty. I connected an external relay to jumper around it and it has behaved itself since then. This was an adaption of a fix on this forum by another member who had the other half of the same relay fail, affecting the heaters in the oxygen sensors in the catalysts.
I have just taken the fuse box out, stripped it down, separated the two printed circuits by cutting the 125 pins joining them, replaced the faulty relay, and refitted the boards together. I will find out tomorrow if my repair is successful.
With these engines, the supercharger coolant pump runs all the time the ignition is on, so if you listen closely by the right hand headlights, you can hear the pump running.
The rationale behind the RP is that without sufficient cooling provided by the pump, the intake charge temperature could rise to the point where detonation and engine damage might occur.
Regards
Pete
Thanks Pete. This is the sort of work-arounds that become important when a marque passes from modern to classic. I had a similar problem with a 1982 Mercedes G-Wagon. Kept cutting out. Appeared to be the replacement ignition switch behind the key that came from Poland. MB no longer stocks the part. Rather than keep ordering questionable replacements, I traced back the wire to the fuse box and ran a heavy wire through a switch to the fused positive side of the battery. Works fine, and keeps the old mule going for another 100,000 miles (it has gone 405,000 miles to date). As I get into Jag owning, I will try to collate workarounds so the forum becomes a pay-forward as the X350s become classics and ageing problems crop up. It is this sort of information that keeps the cars out of the wrecking yard.
As I get to know the X350, I'm beginning to appreciate that the base model XJ6 may actually be the better model to go with because of what it does not have. It sounds like the supercharger adds challenges as you are encountering. I've already discovered that the base radio can be replaced with a modern Android to get bluetooth cell phone, GPS, reverse camera whereas the premium models are tied into the climate control system, thus one is locked out of that upgrade. The 3.0 engine is surprisingly efficient, getting better mileage than the 2007 Volvo V50 the XJ6 replaced. The XJ6 does not burn rubber, but overtakes on our 2-lane roads quick enough. There are a few bits it needs - convex mirrors for a start, or replace the rear view mirror with a video screen and 165° camera, and a second key, but the main thing now is to understand how the computer system works so I'm not chasing symptoms, but actually understanding how the whole thing works together.
Hi Meirion1,
I used a pair of side cutters, and after they were all cut, I separated the boards. Then I used a soldering iron and removed the stubs from each pcb. Some of them were quite tight in the holes, as the pins are square (like a large wire-wrap pin) and push into round holes, in almost an interference fit.
In retrospect, what I would do the next time (which I hope never comes) is use a cutting disc on a Dremel, and just cut each pin in the centre. The pcbs are actually spaced by a square plastic spacer which has pins that click into holes in each pcb. So when reassembling the pcbs, they are kept in alignment by the spacer. In the photos you can see the spacer pins at bottom left and top right on the top pcb, and top left and bottom right on the bottom pcb.
After changing the relay, I would just solder each pin back together in the middle. That would be much easier than cutting enough pins from 1mm round solid copper wire and soldering them into the 250 or so connections.
Having said that, I have now fitted the front power distribution box to the car and all functions appear to be correct. I did have a fire extinguisher on hand, but it was thankfully not needed. The main objective was to make the supercharger coolant pump run, which it now does, without the external relay I wired in last year.
The small relays on the pcb are available from China via AliExpress for a few dollars each, as they are no longer made by the original supplier (Tyco). The only difference is that the contact material is slightly different, but the electrical characteristics such as coil resistance appear to be the same. They are even marked the same, right down to having 'Portugal' printed on the case. If anyone wants the product codes at AliExpress, I can provide them.
As I get to know the X350, I'm beginning to appreciate that the base model XJ6 may actually be the better model to go with because of what it does not have.
x350,
You are right in a practical sense. I didn't go out looking for my car, it came to me. I already had the V12, and wasn't really using it much, so Jaguars were not on my radar. A friend who has a business importing exotic and expensive cars took my car as part exchange for a Jaguar F-Type he was selling. The XJ had a few issues, that I offered to help him with, but after looking deeper at the problems, he ended up selling it to me, as I could sort it out in a leisurely fashion. He of course needed to move it quickly to make a profit, and niggly issues make a car hard to sell. It was only after I got it, and checked out what it actually was that I realised what a bargain it was. I'm about to get the trans fluid changed, and may change the spark plugs, but I used it yesterday after fitting the distribution box, and it behaved itself, so I'm nearly there after about 20 months.
Can't help much (even though I'm a retired electronics tech), except for a shot of the mentioned Mt Ruapehu.
The road goes up to about the snowline, though is sealed and no big deal. (this is a "summer" shot though)
My 3.0 has had some cooling hoses and header tank replaced, at great expense of course. Electronics aside, "happening uphill" suggests a cooling problem?
Yes it's hard to imagine these cars becoming maintainable "classics". Jeez-even CD's are more-or-less obsolete.
(I'm impressed with your observations in your first post. Even OBD might become obsolete, and has certainly had several upgrades. Wreckers yards?)
Another note: Archibald & Shorter AK refused to service my car. It's just a fact, whether Jap Import or they were just too busy would be guessing. I went to Jaguar Workshop, who have been OK so far. Of course, genuine parts are consistent with a (100+G) new car!
I commend your noble and ambitious initiative! To compile an exhaustive database that answers all of your questions would fill tens of thousands of pages.
The "Restricted Performance" warning on the Instrument Cluster is a catchall for many possible malfunctions that cause the Engine Control Module, Transmission Control Module or Anti-Lock Brake Module to impose default settings to protect the vehicle from further damage. The list of possible causes is very long.
The good news is that many of the answers are already available from existing references such as the ones listed below.
1. The Diagnostic Trouble Code (DTC) Summaries manual, an extended version of which can be downloaded at the link below. You won't find the term "Restricted Performance" in the manual, but you can use the Adobe Acrobat Reader search function (Ctrl+F or Cmd+F) to search "Limp Home," "Limp Home Mode," "Restricted," "Limited," "Inhibited," etc. to find faults that cause control modules to enter protective default modes. You'll find that some Limp Modes are Mechanical, and some are Electronic. See the Default Action for each DTC. These are the official Jaguar definitions and possible causes of each code, which often differ from generic OBDII definitions such as those listed in post #4 (many of which are not implemented on the Jaguar X350).
2. The Jaguar Factory Workshop Manual, available from this forum's download area in six sections at these links. The FWM provides pinpoint tests for diagnosing the cause of many DTCs.
3. Jaguar Engine Management System Training Manuals such as the ones at the links below. These describe all of the sensors, their functions, and how the ECM uses the signals from each sensor:
5. Technical Service Bulletins These contain knowledge gained after the initial service documentation was published and vehicles entered production and use and pattern failures emerged. Many X350 TSBs are available in the download area of this forum and at our member Gus' website, jagrepair.com
6. DIY Owner Accounts available in this forum, which frequently report resolutions to malfunctions that are not listed among the "Possible Causes" listed in the DTC Summaries or Workshop Manual. Many of our members are intelligent, talented, experienced DIY diagnosticians and mechanics who are passionate about Jaguars and often find solutions to malfunctions that even Jaguar dealers don't know about. These accounts already fill tens of thousands of threads at the Jaguar Forums, where they are, to a great degree, organized by topic and easily searchable with google or the forum's Advanced Search function.
Diagnostics for the DIY Owner Attempting to diagnose any modern vehicle without an appropriate scan tool is a virtual guarantee of wasted time and money. Fortunately, for around USD $20.00 you can acquire an ELM327 bluetooth (Android) or WiFi (iPhone) OBDII adapter and the Torque Pro app (Android) or DashCommand app (iPhone) and read and clear Powertrain (P-prefix) DTCs, and view Live Data and Mode $06 data. For $80.00 to $200.00, the iCarsoft dedicated Jaguar Land Rover scan tools receive good reviews from our members. For $160.00 to $400.00, the Foxwell dedicated Jaguar Land Rover scan tools are also well-reviewed by our members.
For serious diagnostics, a bi-directional scan tool that can read the proprietary Jaguar Powertrain (P-), Chassis (C-), Body (B-) and Network (U-) DTCs is not a luxury but a necessity. These include the Jaguar Land Rover IDS/SDD systems used by the dealership service departments, high-end laptop-based systems like AutoEnginuity and AutoLogic with the Jaguar enhancements, and high-end scan tools from Autel, Launch, SnapOn, etc.
One thing to keep in mind is that Diagnostic Trouble Codes do not necessarily mean that a specific component has failed, but rather that something in a system has failed or is not performing properly. That could be a wiring fault, corrosion on electrical connectors or ground points, a power supply issue,etc. What DTCs do is help narrow down the diagnosis, but actual diagnosis by the technician is still required. Owners who throw new parts at DTCs without fully diagnosing the cause quickly learn that it can get very expensive and not resolve the true underlying issue.
I hope the documents linked above will answer many of your questions and form a solid foundation as you continue your X350 journey, and thanks for sharing the information you've been gathering as well!
I have yet to find a list that gives all the Jag codes, including hexadecimal which often come up. The links in your email are not happy unfortunately.
I have yet to find a list that gives all the Jag codes, including hexadecimal which often come up. The links in your email are not happy unfortunately.
Hi Edward,
I do have a manual with hexadecimal Mode $06 info. I'll find it and post it here. I just checked all the links in my post and they work for me.
See the attached DTC Summaries manual that includes hexadecimal Mode $06 data on pages 12-13. The DTCs in this manual are organized by system rather than in numeric order, so it's not the first document I consult, though it is searchable using Ctrl+F or Cmd+F. But it has some very helpful information not found in most other Jaguar documents. The only other downside is that the info may not all apply to the X350 and later models.
Regarding the links in my previous post, I have no trouble pulling them up using Firefox. If you're using a different browser you might try Firefox.
Cheers,
Thanks again Don.The link to the DTC manual, first put in your previous post, throws up a blank tab in my Firefox, which confused me. It also downloads the manual.
I have downloaded the one with hex codes which will help. It also has other interesting info in it. I still have to find one with the hexadecimal values. I was using, possibly SSD, that showed both the decimal and hexadecimal codes in its documents. Can't find where I saw it however.
An example of a code I get: Hex FFF6, Decimal 65526, Display U3FF6. All the same code in different formats. Where would one find U3FF6?
I found these in a SDD trace. As well U3FF6 shows up in fault code list in SDD.
An example of a code I get: Hex FFF6, Decimal 65526, Display U3FF6. All the same code in different formats. Where would one find U3FF6?
I found these in a SDD trace. As well U3FF6 shows up in fault code list in SDD.
I've also seen U3FF6 in SDD before, but have not found it in any Jaguar or Ford documentation, though some Ford DTCs related to control module / power distribution are similar (see the attached document). My guess is that it is a hidden code for use by Jaguar engineering but not dealership technicians. Possibly from the Engineering Test Mode menu. Or it may be a corruption due to a programming issue, either in a vehicle module or SDD.
A cheap setup for viewing Mode $06 data is the Torque Pro app and an ELM327 OBDII adapter. With Torque Pro on an Android phone you can read the minimum and maximum acceptable level for each Mode $06 monitor and the current level. This can be very helpful in understanding why, for example, the Comprehensive Component Monitor will not reset, or to see if a particular monitor is running near its limit and is likely to trigger a DTC, or if a repair was successful and a DTC is not likely to retrigger.
01-07-2021, 05:54 PM
Understanding the electronics related to restricted performance
