In my continuing effort to get my cruise control to work, I had a local indy run his IDS on my car. While I am not totally satisfied with the results, it does seem to confirm that my problem is that the ECM is not receiving the necessary input to enable the vacuum switches. There appears to be a failure in the CAN bus, IDS claiming no communication with the TCM, while my AutoEnginuity shows no input from the Instrument Pack. But the car runs and shifts OK with no codes.
I am in the process of tracing the CAN bus for continuity and need to locate the plug on the gear selector switch. Can someone tell me if this plug is accessed from underneath, or do I need to remove the cover plate on the console?
RJ____________
97 XK8 86K mi

 

Found the switch. Thanks again to Rev Sam for the video on removing the bezel. The first time I did it was a challenge, but this time was only difficult. I'm sure I will find the CAN bus circuit is good, but I have to look.
Then it becomes a question of how badly I want the cruise control. It can quickly run into money to have a professional shop with IDS search for a communication problem with no codes for a hint. I definitely don't want to start throwing parts at it, especially control modules.
RJ_____________
97 XK8 86K mi

 

Look at the brake switch. Cruise does not work with a faulty switch.

 

Thanks Bob, but that was one of the first checks.

 

Found a problem. There is no continuity in the CANbus between the gear selector switch and the ECM. The circuit runs through connector EM1, which also has a couple of wires from the A/C control module. Now I just need to find that connector.
RJ________
97 XK8 86K mi

 

I found EM1 and now I'm not sure if I had the right pins when I thought there was no continuity. Anyway, it's good now. If I still don't have cruise control it may well be a module problem, but I don't think I want to invest a lot of money in fixing it. No long trips, my old hip joint and long legs result in cramps, and I can't move the seat back any further.

 

This problem is finally resolved. Going on the assumption that the fault was in the CAN bus, I cleaned every connection from the instrument pack, through the gear selector module to the ECM. Then I cleaned the cruise control switch connection again and put the original TCM back.
I have not had a problem since mid-October.

 

Wow, i hate to see the gambit of parts you had to remove to do all of that cleaning! You must be good at puzzles.

 

Hi.
Sorry to wake an old thread, where did you find EM1? I'm trying to fix a battery not charging issue.

Thanks.

 

You are really taxing my memory. I think it's in the passenger footwell, accessed by removing the panel in front of the door.

 

Nothing wrong with your memory. On side of the right side footwell there's a trim panel, remove that there's 6 x multi-connectors. Was it the white one top left as you look at it?

 

I'm pretty sure that's it. If there is a yellow and a green pair slightly larger,those are the CAN wires. With a magnifying glass you should be able to read the pin# EM1, etc.
I wasn't sure which side of the car it would be for you, thought it might be left side with everything a mirror image on US spec cars.

 

Sorry I didn't get to this until today, so you're way ahead of me. Thought I'd take a pic while I was in there; RHS footwell. EM1 top left. So much for location being 'engine compartment'..
Given its location/environment I'd expect the big 50-way plug that is actually in the engine bay to be a more likely source of trouble.

The cover panel is meant to be removed by sliding towards the rear of the car. However, unless you have the door seal out of the way it's tight,
and there is a hidden fastener that I managed to break

Mike