Hi Guys

Need some help. You may or may not have been following the trials and tribulations of my cruise control issue where I have not been able to trace the problem. So I eventually found a place where I could get the unit tested and they have found that there is a strange fault that prevents these error messages from coming up and the unit does appear to have a fault somewhere...

I have an ECU of another 1999 XKR that I got very cheaply just in case. It is under a guarantee too so bonus. Same numbers as mine exactly.

My question is, how easy is it to swap the ECU? I have JLR SDD.. Is it doable?

Also... does anyone know how to do it?

I'm not happy about not putting my old unit back on but needs must...

Thanks for your help...

 

Pulling the ECM is easy, was on my 97 when I sent it out to be rebuilt. I think the Trans computer sits in front of it. I THINK I pulled mine (trans unit) out of the way, don't recall if I left it connected or not but I know I did remove the ECM with some ease, but that was in 09 so it has been a awhile.

 

I think dannio is concerned with the electronic aspect, not the physical.

If motorcarman sees this he will probably be able to give a definitive answer, and you might even send him a PM.

Having the SDD should make it possible, and I would go ahead and give it a try. Just remember to disconnect the battery before proceeding.

 

Hi Yep, its to do with putting another ecu as a replacement to mine...

I shall drop a pm to motorcar man and see if he can help..

Hopefully he can

 

Keep key compatibility in the discussion. Jaguar implemented a pretty strong anti-theft design into their cars. A ECM change will result in the key not matching the software and require a $400 visit to a dealer to get it to start. That includes the flat bed tow.

Having the ECM repaired may be the most simple solution. Repairs to the ECM often allow plug-n-play reinstallation.

 

Thanks, that is as much as I feared... I will get them to repair the unit and see what happens...

Not going near the car with the back up unit until I know I can do something with it with SDD..

I hope it is plug and play back in...

 

I sent a PM to you and I hope I answered your question about "IMMOBILIZATION SETUP'.
You can install the ECM and if the engine does not start, then you will need to perform the IMMO setup. You can re-install your original ECM and run the engine IF you don't configure the replacement to the car.

If you do configure the replacement to the car then it is 'paired' to that car. If you want to reinstall the original ECM, then you will need to perform the IMMO setup AGAIN to get the car to recognize the ECM. The car will ONLY recognize ONE ECM at a time.

bob

 

Thanks very much for your help Bob.

I have JLR SDD with Mongoose cable only.. hoping that will be enough to update and get control back if I need to. Will wait till the 'repaired' unit comes back and see how things go. Will keep you updated.

They guy working on the unit said this:

1. On auto testing your unit functions for outputs OK

2. On manual testing all output functions work OK (I did this myself)

3. I have found a fault thou, if you disconnect anything to the dash (combi). Your unit does not log a faultcode.

4. I have disconnected several sensors on the input breakout lead, engine based, and it does log "drive phase voltages errors"

5. I conclude....

You have not found the fault relating to cruise control on the host vehicle.

You are also not getting any reliable faultcodes to assist you with this task.

6. I will now move to "bank the chips". Compare files sizes for errors.