do you have full throttle authority key on engine off and on

the new mystery pcm added gasoline to this dumpster fire of a situation

 

Two questions:

Was that pressure verified with a mechanical fuel pressure gauge?
When the car shuts down is it still showing 46,6 pounds?

One of the modules that you can't communicate with is the KTM - the Key Transponder Module. Maybe the car can't verify the transponder chip in the ignition key as a result?

 

What you are saying is that the new "re programmed ECU" is expecting a different key code. ie the key chip from the car that the new ECU came from.

 

Have you tried to reprogram your keys via the jaguar software.
My 1998 xjr was inoperable for 2 years, I was away overseas working for 1 year. Car spent 3 months with so called jaguar independents that really did not know what they were doing.
Problem is that people tend to read the codes and take them literally which is not the case.
from memory i had 1260 security up but my security system still functioned via fob and security light nesr gear lever. Also had a transmission can failure logged.
​​​​​My car would not crank but everthing else worked.
I had a key man come to cut and program 2 new keys for another car X,J8 I bought which was a drama in itself but eventually was successful.
​​​​​We discussed my issue with the xjr after trying to jump start it (flat battery). He had the jaguar software and we confirmed the codes from my reader. We wiped the existing keys and did a key reprogram and it started first go after sitting for 2 years. The so called jaguar independent experts didn't even try this. I assume your run stop issue makes no difference which key you are using.
A key reprogram is worth a try.
​​​​

 

According to the 'Immobilizer' section of TSB 100-22 03 XK specs (attached) , the car won't crank if the key isn't recognised.

 

When the key is turned to just before start (system check moment) proper voltage is applied engaging all vital relays throughout the car. ECU, BCM, KTM, etc etc etc. It also fires the fuel pump for a few seconds. Many things. It's a hard old school electrical connection in the key switch. Ball bearing and spring loaded.

The second you turn the key to start (engage the starter) that connection is broken, and then reestablished when the key is released completing the connection and reestablishing the circuits for all mentioned systems/relays above. Anyways, it does this with a handful of relays (the ECU has its own) in the different fuse boxes around the car. ECU relay lives right next to it.

When the key is turned OFF, everything immediately shuts down... Q: what happens in the dash when the car shuts off? Does it go BLANK? Any signs of life? What signs life?

The car might not produce a code(s) (except ones similar to the few mentioned in the first posts of this thread) or none at all because it simply thinks it (the car/relay) was shut off "normally",,, IF the relay powered down because it is faulty. Is there a such thing as failed relay codes?

​​​​​​I think (and have been wrong a million times about a million things) the problem is simpler than what's being tested for. It is a great learning experience though.

 

Thank you so much for that, I didn't know what the KTM was on the jaguar diagnostics, and it is the Key Transponder Module.
In the PDF file you sent it does not say that the engine will not crank, it says, the ECM controls Fuel Injectors, Ignition Coils and Fuel Pump. The timing of the start and then shut down is so identical each time that this may be the issue. Now I have to figure out how to get the key transponder module showing green and connected in the diagnostics.

 

I don't know if this is doable or not but this is a link to the video I put on Facebook

 

when the ktm doesn’t see a valid key transponder the bpm will not enable the starter and you will get a p1260

when the ktm and the ecm are not paired to each other you will have injection disabled and a crank no start. you will also get a p1260 at least on aj26/27.

when you turn the key to START does the fuel pump run?

 

For the sequence and order of "OK's" have a look at figure 3.1 in the attached PDF... I am pretty sure that if the KTM is not active or recognizing the key,,, the car will not crank, fuel or spark...

 

I tried to parse the link to repair it, but couldn't succeed. Please try sending the video link to me in a Private Message and I'll see if I can add it to your post.

Cheers,

Don

 

The Instrument Cluster is a major player in starting but its role in running is never discussed. It is the one multiplexed module that speaks in two languages, the SCP and CAN systems so it communicates with the BPM and ECM. The Instrument Cluster "Passive Anti-Theft System" gives "Security Status" to the BPM over the SCP lines. It also uses the CAN Bus to relay "PATS Generator Warning" to the ECM but it isn't clear what role that plays after starting.

The Key Transponder Module (KTM) will perform a challenge/response routine with the
key to determine its authenticity.
· The Body Processor Module (BPM) will transmit the Standard Corporate Protocol (SCP) -
Key Valid message containing a unique three byte number to the Instrument Cluster. The
Instrument Cluster upon receipt of this message will compare the data received against the
unique number stored in its memory. If the comparison matches, the Instrument Cluster will
set a flag to confirm valid key received. If the comparison does not match, the Instrument
Cluster will set this flag to invalid.
· If the ignition key is turned to the Ignition Run position, the Instrument Cluster will start the
data exchange and start transmitting the idle status. If the key status is valid, and the
subsequent challenge/response is verified by the Engine Control Module (ECM), the ECM
will allow the engine to start. Otherwise, starting of the engine is disabled.
· The ECM controls the following outputs: Fuel Injectors, Ignition Coils and Fuel pump.

from 2003 MODEL YEAR XK SERVICE TRAINING TECHNICAL GUIDE
The immobiliser system prevents an unauthorised attempt to start the engine. The Key Transponder Module (KTM) transmits a valid key status only after an authentic data communication has been performed between the KTM and the transponder key. When the key is turned to the Aux ignition position, the KTM energises the coil, which in turn starts a data transfer with the transponder key. If the code received matches a code stored in the KTM EEPROM, the KTM will perform a challenge / response routine with the key to determine its authenticity. Once the KTM has authenticated the key code received, it will send a “Key Valid” message to the BPM via the dedicated ISO Data link. If the key code does not match one stored in the KTM memory a "Key Invalid" message will be sent to the BPM. The BPM will transmit the SCP – key valid message containing a unique 3 byte number to the instrument cluster, the cluster upon receipt of this message will compare the data received against the unique number stored in its memory. If the comparison matches the instrument cluster will set a flag to confirm valid key received. If the comparison does not match the instrument cluster will set this flag to Invalid. If the key is turned to the ignition Run position, the instrument cluster will start the CAN data exchange and start transmitting the idle status. If the key status is valid, and the subsequent challenge / response is verified by the ECM, the ECM will allow the engine to start. Otherwise, starting of the engine is disabled. The ECM controls the following outputs: starter relay, fuel injectors, ignition coils and fuel pump.
The ECM will disable the fuel injectors, ignition coils, fuel pump drive and starter if any of the following conditions apply: • A theft signal has been received from the IC, i.e. the key code has not been received/code does not match. • A challenge code has been transmitted to the IC but no response code has been received. • A challenge code has been transmitted to the IC and an incorrect response received. If any of the above cases apply, the ECM will log DTC P1260. This DTC is further defined by sub-codes. The sub codes are accessed through freeze frame data. Additionally the IC will log DTCs if the failure was a result of the key transponder exchange.
2003 MODEL YEAR XK SERVICE TRAINING TECHNICAL GUIDE
I've investigated but found no answer as to where, in the sequence of events, the initial prestart fuel rail priming occurs. The Immobilizer sends the "OK to fuel" signal to the BPM but does that have to run through the Instrument Cluster to the ECM for the 2 second priming? Probably, since the BPM only has one direct connection to the ECM that is the "Request to start." You'd have to think all the immobilizer protocol has been satisfied and no longer a factor or there'd be a P1260 or other error code.

I realize it has been said the technician originally verified fuel pressure, but could that mean only priming pressure? I'd like to see the pressure gauge, or check voltage on the pump as it runs and then dies . The ECM monitors the fuel pressure and shuts down if there's an anomaly which could explain the instantaneous shuts down. We probably would see a code if that were the case.

I have to wonder if there's a subtle, underlying condition that gives a false theft alarm to the Instrument Cluster causing shut down. You'd have to think it would not even try to start if that's the case.

I posted my own problem in "NO CRANK mystery & misery" and detailed how I rewired earbuds into a dirt cheap cell phone oscilloscope harness where I viewed signals directly on components and also used a siamesed ODB2 extension as a breakout box to observe the SCP and CAN signals in real time. That ended a lot of my guesswork.

 

all it does is imitate the real PATS that’s on the 202/350. you will still get a P1260 and a fuel inhibit

 

I ran down the list of all Diagnostic Trouble Codes and there aren't any that shut the engine off. They may prevent starting or limit performance, but no shut downs. It would seem with this bit of info and the issue that there are no telltale Codes stored, the shut down is not related to the immobilizer feature nor an ECM detected problem. I don't know of any combination of actions that could bring on an anti-theft lockdown or something else we've overlooked. I don't see how any other module, particularly immobilizer, PCM or Instrument Cluster could order the ECM to shut down.
Powertrain DTC Summaries – EOBD
Quick Reference Diagnostic Guide
Jaguar XJ Range V6, V8 N/A and V8 SC
2003.5 Model Year

As expressed before, we can suspect the software in the replacement ECM. If you have the original, can you reinstall it? Even if it runs rough, that'll indicate the replacement ECM's instructions may be corrupted. You can then return the pair to the programmer or find someone else to rewrite the firmware.

My only other course of action would be to pull out my cell phone and oscilloscope cord and determine whether injectors and/or coils shut down after 2 seconds and observe the SCP and CAN activity off the OBDII siamesed extension for clues.

XK Range
2003 Model Year
Electrical Guide,,,,,, has wiring diagrams and electrical details I refer to frequently. The appendix has a matrix that sheds light on the interaction of modules and buses through pretty much all interactions.

Maybe this winter, I'll set my new Mongoose clone cable up on an old XT laptop, then hope I never need to use it.

 

It's something simple

 

There seems to be a significant change to the immobilizer system in 2004. I have a technical information bulletin that says that the immobilizer shuts down the fuel pump, ignition and injectors which seem to be what is happening. I took the back end of the car apart to get at the KTM, the key detection module, as a number of suggestions were to check that for grounds and different colored wires. My module readout from the mongoose gave me a Module not detected notice.
This car does not have one, it seems in 2004 it was integrated into a module that is located under the trunk fuse box, it has an antenna on it. My key fobs do everything they are supposed to. Lock unlock car, sound alarm etc. so I know the fobs are connected. I put a jumper on the fuel pump relay as someone suggested and it continues to run after the shutdown and shows 46.6 pounds on an I-soft OBDII diagnostic, so I have ruled out the fuel pump.
I think I need to find out specifically what the RF chip in the key is talking to do. It is definitely something new in the 2004 model.

 

The KTM is located behind the HVAC vent just to the left of the steering wheel in when sitting in the driver's seat. It's easiest removed by removing the instrument cluster, the surround of the vent, the vent air directional and some other stuff. You'll see it. You'll need small torx screws to remove the fasteners and a few curse words.

The SCLM is under the main relay/fuse box in the boot. Remove all the shelves and the spare, unbolt the 4 10mm bolts and the thing should be "easy" (not) to manage. The SCLM is a grey box under the fuse box. Held by clips.

The fuel pump control module is also in the boot, to the right of and over the battery. A little bigger than a cigarette pack. Silver, labeled, 6 wires coming out of it. Two very skinny, a black, a brown, a yellow/red and a red...

 

!997 introductory model year had no immobilizer. In 1999, they introduce the immobilizer that was much less complicated and used an RFID chip that had a precoded number. In 2003, they complicated that system and went with a much more sophisticated chip. The 2003.5 DTC... and 2003... Electrical... guides referenced above ran through the 2006 model.

Nice job on jumpering the fuel pump to eliminate one more unknown.

You posted " I have a technical information bulletin that says that the immobilizer shuts down the fuel pump, ignition and injectors..." What TSB is that? I've never run across the immobilizer shutting it down, The ECM just refuses to activate fuel/spark/starter when the key is turned. My intepretation of the limited information on the subject would be the engine never should have started in the first place if the immobilizer system flagged a fault.

One lingering question in the back of my mind is will the fuel pump primes the fuel rail if the immobilizer system is not satisfied? Does it prime before or after the KTM/BCM/IC series of events?

The ecm is the orchestra conductor of the fuel pump, ignition and starter. One would assume it is the ignition shutting down thanks to the ECM but is the ECM the problem or some outside influence. Is it possible to reinstall the original ECM and see if it continues to run?

Hang in there!

 

The car shuts down after running a couple of seconds with no stumble like fuel, just like it has been turned off with the key. It always reaches 1100 rpm before shutting down. It seems that the 2004 has the KTM, the Key Module shows as not responding. I opened the back of the car between the taillights and found this car does not have the module there. Noe someone else on here tells me it has it has been moved to somewhere behind the speedometer. All of my key fob's function as they should locking and unlocking the car and sounding the alarm. I am waiting for British Diagnostics to get back to me as I am supposed to be able to get in and check the modules with the mongoose and their software but the Service functions do not work.

 

The KTM is not a part of what is happening with the key fob and basic car alarm stuff.

The KTM receives a signal from the "exciter ring" (exciter ring reads the CHIP in the key) in the cars steering column. The exciter ring then sends that signal to the KTM... The KTM then signals all cooresponding components that all is OK to start.