ACC Module - Expert Advice Sought!
 

Hi Everyone,

I'm hoping I might be able to pick an expert brain or two here!

I have the dreaded "Cruise Not Available" in my 2002 XKR - which is supposed to have ACC. It's always been there, I naively bought the car without doing my proper research into how much of a pain in the a** this might be to get this sorted.

So anyway, yesterday I decided to whip the module out and have a look. Two things of note:

1. When I started the car without the module in, the car went into "Failsafe Mode" and I think a couple of other errors came up. When I put it back in, it went back to just cruise not avail (interestingly, I usually have to drive the car for a hundred yards or so for that to happen - but it immediately comes up with no module in).

2. The part I took out had the part number: LJE-1960-AB ...... BUT, what I thought was interesting was that that number was also scratched into the metal of the part by someone else. Now, I'm thinking, that, that's the sort of thing a scrap dealer might do if they thought the label was getting faded (which it was)... but I can't really imagine a normal punter doing it, then putting it back in (if you see what I mean?)..

So, two questions:

1. Is the response to unplugging the module in point 1 what you would expect? and...

2. Is it possible / likely that someone has bought a replacement part from a scrappy and plopped it in, but potentially put the wrong / incompatible part in... I have looked for part lists etc, but not come up with much of any use? Might this cause the symptoms above?

Thanks so much for anyone who can help / provide advice. This is about the only thing wrong with my lovely car and I don't really know what I should do about it - (particularly as I'm questioning exactly which part number I should be looking for and they seem hard to come by anyway!)

Best Regards
Andy

Oddly the first suspect is your battery.
A feeble battery can cause all manner of problems including this one.
https://www.jaguarforums.com/forum/x...lable%22-7933/

Thanks Steve, the car starts on the button etc and there's no obvious signs of the battery not being up to scratch.. BUT, I suspect you'll say this might not mean anything :-) ! What's the best way to test? Stick another in and see? I have no other errors or faults....

The best is to take it to a tyre + battery place for testing but you'll get some idea from measuring the voltage at the posts with the ignition on + engine not running.
It might not be the problem but it is an easy fix.

Thanks Steve, I'll check that out. What should the voltage be? 13 or so?

Does anyone else know anything about the part number by any chance?

Cheers!

12.4 is good enough.

Also, a bad Stop Light Switch can cause this.

There are 2 sets of contacts on the switch. Even though the N.O. contacts are OK, the N.C. contacts (used in the Cruise Control Circuit) can fail.

This is the switch that is "Fun" to replace.

Update
 

Just to keep anyone who has the same issue updated.

After a lot of googling etc, it seems that the particular module with the part number: 2W98-9AA12-AA (or AB I think) has a known issue causing this fault. I spoke to BBA Reman who say they have (so far) had a 100% success rate in fixing this issue and it costs around 600GBP - way, way, way less than a new module which is over 2K I think.

As soon as I get round to sending the module off I'll report success or failure!

Regards All
Andy