I am a bit panicked , recently bought an 05,xj8 and very excited, after all my years of sacrifice i can finally have a decent car . The car was sitting for 2 years from the previous owner for two years and the front was sitting low so i had someone look at it and they stated it's probably the front struts so i just changed them today from a car that was working so i am sure they are good , unfortunately they are down and i now cant even hear the pump turn on and they are low riders up front . I dont have the funds to go the dealer and maybe i don't have to but i do need some advice, i saw an earlier post that stated drive the car around the block for a few minutes at 2MPH and that should get the pump to initiate . The 40 amp fuse is good so i am at a loss, i am in whither , ca and in dire need and freaking out a little .

 

Do you have any code messages?

 

Alli get is suspension fault , i think i might try get a code reader myself .

 

Was the compressor working before?, If the car has been lying for 2 years unused, it could be the compressor at fault, or even the distribution mainfold, compressed air will have moisture in it, and if left to sit for a long period, that moisture will turn to rust so the manifold could be blocked, or the compressor could have seized up, might be worth taking those parts off the car you got the struts from.

 

Bad news, most code readers will not give you the codes you probably need. They will only give Powertrain (P0**) codes and maybe some ABS codes. You may have to get the Jaguar SDD program through this site. I would spenf the money for a tester on a Mongoose cable. There is lot of information about that program on here and you will probably the SDD if you do your own work anyway. Download the Workshop handbooks for the Chassis, Electrical and General Information first, then read the sections regarding the air suspension components. Also search for ASM issues on this forum. I believe there are other fuses that may need checked. If you have a decent circuit tester you may be able to troubleshoot some of the modules and related circuits, relays etc. without reading codes and from what I can tell the electrical values for everything is in the handbooks (they are large). I am going to guess that you had to put in a new battery when you bought the car but have you done a hard reset since you installed the shocks? There may be several things you need off a donor car but you may need to test them to see if they are any good, hence the tester and the handbooks. Can you get any information about the condition of both vehicles suspensions?
Good luck and keep us informed. Congrats on your purchase. Once you get it sorted you will be very happy. That said these autos are computerized to a fault and depending on your ability can be fixed by a confident DYI'er. Otherwise you may need a good independent Jaguar mechanic/shop.

 

got the bad news , there is an electrical issue so there is no communication between the air suspension and the main computer, price to trace and resolve $1000.00. This is to only fix the communication issue, if the pump or anything else is broken there will be additional cost,not what i was looking to hear but i least i know. I am looking for some cheap recommendations to switch over to coil, i don't mind the light being on on the dash just need to get car on road and begin to enjoy.

 

Who told you that ? There is no "main computer". The air suspension system is controlled by the Air Suspension Module (ASM) located behind the back seat. This receives height messages from the height transmitters on the front and rear suspension and then adjusts the vehicle height by adding or subtracting air in the air springs until the transmitter readings match what it has in its memory. As well as controlling vehicle height, the ASM controls the adaptive dampers. It receives data via the CAN bus like speed, engine revs, torque etc so it can do this.

However, like many owners in the USA, you can buy kits that convert the car to steel coil suspension, but you lose the adaptive damping. Most owners are not concerned about this. The problem with these cars is that if you get faults like you have, you need a technician with some experience of the cars.

If you have got "air suspension fault" displayed, there will be codes related to that, so if you can tell us what they are, some advice can be given. At the moment we're as much in the dark as you are. My money is on a duff front height sensor.

 

As per the tech he says its not getting any power , i am trying to swap the ASM with one that works and see what happens. The next step if that fails, coils

 

When a car has been sitting for a while, it's not the electronics that go bad, it's the mechanicals. In SoCal we also don't get a lot of corrosion. Swapping the air suspension module is tricky. You'll need a genuine SDD and VCM to do the reprogramming and even then it's difficult.

What's going on with the rear suspension? If it's at normal height I would try to weigh the trunk down to see if it rises, or lift the rear a little to see if it lets out air. That will tell you right there if the module is working.

All air coming in or out happens at the pump which is located right in front of your left front tire.

I would also definitely drive the car around to see if the pump activates.

The two main problems with the air suspension are shocks leaking and pumps failing.

 

Thank you all for your suggestions as I go through this very frustrating time, this weekend its been raining and I spent over 10 hours reading different post about these air suspension units and the best I can figure out, there are issues . So while reading I came across a post that seems to make sense financially but I am not sure it will feel on the road. My goal is to enjoy the car and my previous car was a Honda so there if there are a few bumps I have grown accustom over the years , not to restore to it factory specifications. There was a post stating that one can adapt the front struts from an 2011 Xj my simply drilling a hole in the frame because the holes don't line up or one can have a machine shop make an end cap with the proper holes so there is no drilling in the frame, please do chime in and let me know what you senior and more technically sound members think.

 

Hi ACharles,

I'm sorry to join your thread so late.

The most common cause of the front air springs/shock absorbers sitting low is an air leak, usually in an air hose fitting, one of the air spring top seals, or one of the air spring bladders (air bags). You have replaced the front air springs/shocks with known-working units, but you may still have an air leak in an air hose fitting, especially if you did not replace the brass compression rings or "olives" on the air hoses. Once you get your compressor running again you can test for leaks by spritzing soapy water on the air hose fittings and around the air spring top seal (just don't get the water on the electrical connector for the ECATS system).

It is also quite likely that the piston ring/seal in your air compressor is worn and the compressor cannot pressurize the system as quickly as the Air Suspension Control Module (ASM) expects, which triggers faults.

Some causes of the Air Suspension Fault will not allow the compressor to run again until the relevant Diagnostic Trouble Code (DTC) is cleared. I have not cataloged which codes cause this condition, but it has happened to our '04 XJR enough times that I am positive this is true.

Before you spend money on a coil conversion or any other parts, I would strongly recommend that you find a good independent Jaguar mechanic with a diagnostic system like SDD (Symptom Driven Diagnostics) as Ranceheroguy mentioned. Knowing which codes are stored will help us help you solve the problem.

To get the compressor running again so you can drive the car to the shop, it may work to do the hard reset Rancheroguy mentioned. To do so, disconnect the negative battery cable and touch its terminal to the positive battery cable terminal (you don't have to disconnect the postive cable terminal from the battery since the circuit will not be complete through the battery). Hold the negative terminal tight against the positive terminal for around 2 minutes to allow all the keep-alive-memory capacitors to drain. This may or may not clear the relevant DTCs that prompted the ASF warning, but it's worth a try.

Worst case, you will need a mechanic with SDD or other bidirectional diagnostic system with the capability of reading and clearing proprietary Jaguar Body (B- prefix), Chassis (C- prefix) and Network (U-prefix) codes. Write down every code exactly as it appears (for example, C2302, U1900, B2810, etc.). Post all the codes here and we'll try to help.

For more information on the air suspension system, see this thread:

Air Suspension & ECATS System Summary: Components & Operation

Cheers,

Don

 

​Thank you for chiming in,i am new to the area so finding a good mechanic that's not trying to rip me off would be difficult since i don't even see a jaguar any where in the vicinity . I will take your advice and do the reset but i need some recommendations of members in California where can i find a good mechanic who knows about the cars and is not looking to take me for a ride. I live in La Puente California, 91744. If anyone has a recommendation,please send me a Private Message.​

 

ACharles,

I removed your personal information from your post since it is not prudent to post information such as home addresses or phone numbers in a public forum. I instead suggested that members send you a Private Message (PM), through which you can communicate in a more secure manner and exchange personal contact info without also sharing it with identity thieves and other miscreants.

Cheers,

Don

 

Thanks, it was desperation

 

I went to pick up the car today from the mechanic , you all been asking what are the codes and here they are:

1. C2780
2.C1830
3.B2810
4.C2302

No signal or power from ECU to relay compressor , based on the estimated repair cost, i think it might be best to try coil on the front . i saw a post about using the 2011 XF front struts, thoughts ?

 

Did you check the fuse? No.6 fuse in the bonnet fuse box.

 

Hi ACharles,

You cannot replace only the front air springs/shocks with coil units because the ASM cannot manage only half the system - it will simply illuminate multiple warnings and shut down.

C2780 indicates that the "ASM needs configuration." By definition, this code means the Air Suspension Control Module needs to be recalibrated using a Jaguar diagnostic service system such as WDS or SDD. However, in your case, it may be due to the other codes:

C2302 is the code for "Leveling Plausibility Error," and it is the classic code for a worn piston ring/seal in your air compressor. An inexpensive fix using a kit from our forum member bagpipingandy.com

C1830 indicates a problem with the air suspenion relay drive circuit, either an open circuit, a short to ground, or a short to B+ battery voltage.

B2810 indicates a "Vent circuit fault." The exhaust vent solenoid on the air compressor is opened whenever the air suspension pressure needs to be reduced or one or more corners of the car need to be lowered, and it is also opened periodically to backflow dried air through the desiccant bed to partially dry and reactivate the molecular sieve beads. There may be an electrical problem with the vent solenoid, or, more likely, it may be stuck due to corrosion from moisture in the air that is drawn into the compressor and accumulates over time.

My suggestion would be to have all the codes cleared to see if the system will try to run. If it won't run, check the air suspension relay (they're known to fail). Once you're sure the relay is good and the system is trying to run, rebuild your compressor, replacing the piston ring and cleaning all corrosion from the internal mechanisms. At that point you may need to clear any residual codes and see where you stand.

Cheers,

Don

 

I just looked at my copy of the Jaguar DTC codes and the entry for C2302 is absolutely identical to C2303. So what makes one come up rather than the other is what I'd like to know.

I reckon the C1830 is the key to the affair. No supply to the relay = no power to the air suspension.

 

Is there a cost effective way to repair this without breaking the bank, the quote i got from the shop was $1000.00. and that's just to get power back to the unit .

 

Find another shop ! A $1000 just to find out where the fault lies is really quite ridiculous. Of course, once there is a prognosis, some parts may be needed. You've already rushed to replace the front air springs at whatever cost just because somebody told you it "probably" was the struts. Time maybe to stand back a little bit and investigate before spending a shedload of dollars.

It's a 2005 car, but what is the mileage ?

Anyway, there are three fuses for the air suspension system: -

Engine compartment fuse box
F6 - 40 amps - for the air compressor

Trunk compartment fuse box
F12 - 10 amps - air suspension
F52 - 20 amps - air suspension

Handbook doesn't say what the two trunk compartment fuses supply in the air suspension system, but one will no doubt be for the ASM control box itself.
I have the wiring diagram for the X350 and it shows that both the compressor relay and the vent valve is controlled directly from the air suspension module. The relay is earthed at the outermost earthing point G2 behind the RH front headlamp and the compressor at G1 behind the LH front lamp.

I've attached the air suspension wiring diagram for you. A competent auto-electrician should be able to trace where it's going wrong, for instance when you start the car, there should be volts at the relay. The ASM is powered up because your getting the fault display and codes. However first thing is to clear those codes and start again afresh.

PS: I forgot the vent solenoid that is likely on the same wiring run from the ASM to the compressor indicating this as the likely source of your trouble. This isn't earthed locally, and if it flags a fault could indicate a high resistance somewhere on the circuit like a corroded connection.