1998 XJ8 BCM/PCM issue.
 

Hi guys, just purchased a 1998 XJ8 knowing the old BCM burned up after ignition switch issues. I've traced the ignition switch wires and can't seen to find an issue or short but the old BCM actually melted. I have a donor BCM and it's PCM. On the off chance that the old BCM was just faulty I attached the new/donor BCM and crossed my fingers. Everything works except the car is a no start(won't even turn over). I know that BCMs should be reprogrammed but if I use the PCM that came with it should that help or do I need a scanner/programmer to fix the issue?

Background, I also have a 2002 XJ8 that I got for a song because the rear main seal was pouring oil and I fixed that my self. Mechanically I'm good with tearing the car completely apart and putting it back together and firing it up. Electronically I hate electrical/electronic issues with a passion.

Welcome to the forums RNJeff,

I've moved your question from X350 to X308 forum. This is the place to post technical questions about your 1998 and 2002 XJ8's.

Graham

From another site... The module does not have to be synchronized and is plug and play. The new module must has the same part number and suffix that is on the old module or VCATS label under the carpet covers in the trunk.

Thanks
 

Only problem I have is that the original module is gone.

Look where the spare tire is. That’s the VCATS label. It has the part number to every module in your car.

Found the label and it's a match thank you. Plugged it in and everything works except for the starter. I have to get under the hood but the latch is messed up and only pops on the right side. When I get that open I'll check the fuses and relays.

You not only have to match the part number but also the 3-digit suffix like, for example, "/013". These suffixes are shown on the VCATS label but, unfortunately, not on the modules. The BCM (BPM) module shows the suffix as "/XXX" and has a note "this part is programmable". Unless the seller has recorded the BPM and the PCM (ECM) suffixes from the VCATS of the donor car, there is no way to know what suffixes the modules you bought have and they may be different from what the modules of your car have. If the suffixes of the donor modules (ECM and BPM) happen to be different, I don't think you will be able to start your car without their re-programming.

That may be the problem then. Everything else works on the car but it won't even try to turn over. So you suggest any place to send it for reprogramming?

First, this old thread... https://www.jaguarforums.com/forum/x...bility-118453/

Ok, don't shoot the messenger on this, its a few years old... ...I would hope someone would say something if this isn't correct so I can get a mod to remove it.

As far as I know, the ECM of the early (AJ26) engines is not programmable. So it is probably better that you keep your original ECM and get the new BPM programmed/configured. I believe that this can be done by any Jaguar shop that has the Jaguar VCM/IDS tool. The BPM configuration has to be done while it is in the car (connected).