I think this will be the best topic for my problem.


I have an 4.0 XK8 MY 2002 with ACC problems. Everytime on startup I have an amber light and "ACC not available". No loss of engine power.


On my Jaguar WDS I get:
In ASCM:
B 1342 ASCCM Adaptive Speed Control Control Module Failure
U 2023 CAN fault message received from other network module
U 2503 CAN IC Token missing


In DSCCM:
C1285 Active brake booster solenoid drive circuit fault
P1627 Module supply voltage out of range


I thought the problem was U2023 in combination with C1285 and so I checked the wiring from DSCCM to brake booster and finaly replaced the brake booster! But with no result .


My question is if this would be the right way to go (aiming for the solenoid fault) or should I go for B1342 and start looking for a new/uses/repaired radar?

 

Seriously talking out of my depth; however, with all due respect to others in the group-I had the same problem and replaced the break switch at the firewall. It is a bear to do and I had to use a chop-stick, be upside down, and have the seat removed to accomplish the replacement. the warning went away and my cruise is back. the switch on my car is a two metal strip connector that is one-on, other off which kicks the break lights on and the cruise control off when the break is used. Apologies if this is a repeat answer.

 

Thanks for you reply. Usually a broken brake switch will give you an fault code, but to make sure I measured the contacts and they were working fine!


After reading several topics according to B 1342 I took the adaptive speed control module out of the car and send it to BBA Reman (after I have had contacted them). They found a broken processor and they were able to fix it (not always the case!). So I had good hope it would be fine by now..... After installing, erasing fault codes and calibrating the scanner still the fault on the dashboard . So back to the WDS, and it gave me:


In ASCM:
U 2023 CAN fault message received from other network module

In DSCCM:
C1285 Active brake booster solenoid drive circuit fault


So I was one step closer but still not satisfied. In my first attempt to fix the brake booster I checked almost everything related to the booster (except the module it self), and I remember (!!) the "P1627 Module supply voltage out of range" code. So this time I checked if the module had all the necessary power supply's (2X) and grounds (1X) and found out 1 was missing. Long story sort, there was a blown fuse and that was causing the C1285. Now the system is working! Not sure why it was blown out but I wasn't the first person who tried to make the system working.


Looking back you always think why haven't I stared with that, but that is the story of electronics at the end there is always a simple fix compared with the time that went into.

 

I had the same problem, the ACC worked half of the time and kept displaying the amber light with the 'not available' message. It turned out a new battery solved the problem, the old battery measured 12.15 volts in the cigarette lighter.

 

Hey guys,

unfortunately same problem over here (ACC sensor blocked). Although I was almost sure it was a temperature issue (message went on and off several times while driving) and therefore thought it might still have some life in it, IDS instantly reports a communication error (ACC and ACC booster).

To be honest I am not very familiar with this software - but does this hint to a 'bad' ACC module or rather a problem between the ACC and the ECM?

Any hints, tips, ideas gratefully appreciated - thanks.

Ekki

 

Hi Ekki, I don't know how to reply to a private message but I can open an ACC module. I used a Dremmel tool with a cutting disc and carefully cut through the White adhesive which as you say is really hard, I did damage the plastic cover a bit as you can see in photos. Where you can't cut with the tool I just used a hacksaw blade and a flat head screw driver and prized it apart. Hope this helps.

 

Thanks a lot, Brizzy.

Probably the first time the world has seen what's inside this box - and it's here on Jaguarforums.com! :-)

I'd say old-school hi-tech at its finest. Trying to repair this without a diagram will going to be a though one...

Ekki

 

Hey guys,

and sorry for rehashing this topic but at this point I'm out of ideas.

The current status: I opened my ACC module and gave it to a (experienced) technician who replaced all the 16 capacitors (prone to age/decay) and checked all soldering points. I guess that's all we could do at this point and I didn't expect much. But you can't complain if you don't even try, can you?
So it was no surprise that I still got a 'Cruise control not available' and IDS still detected a 'communication error'. As expected but still disappointing.

BUT (almost unbelievable since these modules are _very rare_ - to put it mildly...) I was able to ****** a module on Ebay this week. With great expectation I assembled the new/used module - but still no cruise control/communication error. What a downer...I spare you the tearful aftermath.

So it is probably not a faulty ACC module. But what puzzles me is how to interpret the IDS data. I have to admit that I am not too familiar with this software, so please excuse my ignorance.
IDS does not detect any DTCs (ACCM related U252X) which I would have expected if the module was faulty. Btw, the radar is audibly moving inside, so it does have power.
OTOH IDS reports this communication error in the module section. Same error (no communication) in the new module adjustment section.

So, as far as I see it the module is (somewhat) recognized but CAN bus integrity is faulty. According to the schematics there are two signals between the ACC and the ECM. So I will check the harness first.

But maybe there is some electronics guru out there who has a deeper understanding of the connectivity.

Thanks!

Ekki

 

Hi Ekki, have you had a look at the brake control module? It's the unit that automatically brakes for you when in cruise control, it's part of the acc system. Location is on the right (UK) inside next to the brake booster vacuum unit. Here some pics of the module.

 

Hi Brizzy,

thanks for the feedback. I guess that's the ASC booster control module (at the right in RHD cars, vice versa in LHDs).
I will take a look at it since this module also generates a communication error.
I also (visibly) inspected the ECM today. No corrosion or any suspicious wiring. Heck, there wasn't even dust in there. Looks almost mint.

 

Ekki, have a look at Gijzzy post earlier, he had the same problem and it turned out to be a fuse.

 

Hi Brizzy,
I checked both (IMHO possible) fuses at both locations (11 & 22) quite early in the process. No luck. That would have been an easy one...

 

Ekki, any update on your car?

I also have the "Cruise Not Available" warning on my XJR. My dealer told me the repair cost is $3,400! I am looking for alternatives and want to make sure I don't miss something cheap and easy.

Thanks!

-Burt

 

Burt,

the new/used ACC-module I bought (for appr. $400) seems to work, well, somehow. At least I don't get any more (amber) warning messages. IDS still reports a communication failure but this might also be a 'software incompatibility'. The only (audible) difference I noticed was that the old module was constantly moving when I turned on the ignition. The replacement unit does not do that.
To be honest I am reluctant to check its function under driving condition. Who knows what's going to happen? Since I never use CC alas not ACC I'm not really missing it and I'm just happy that I got rid of the warning msg.

My take: a broken '1st generation' ACC-module is probably the worst thing which can happen to a Jaguar-owner. Almost no supply, besides there are no real experts for this out there.
Since (AFAIK) Jaguar no longer sells this as a spare part, the 3.4K 'repair' probably means a complete replacement/upgrade to a newer ACC, including new modules, etc.
If you don't want to spend this kind of money (I wouldn't) I would frequently look on Ebay, for-sale ads in forums, etc. Painful, maybe in vain.
Before I bought the new/used module I contacted these guys -
Welcome at ECU Repair Centre, your adres for repair of car electronics, like ABS, Cruise Control, Ignitions modules and many other ECU's
They told me that a repair would cost appr. €350 or €50 as a 'testing charge' if the are unable to repair it. If you are out of other ideas this could be worth a try.
Send me a PM if you need help.

Good luck!

Ekki

 

Hi Ekki,

Thanks for the update. That is fantastic news. I am on the opposite end of the spectrum. The number one reason I bought my XJR was to get the adaptive cruise (and a fast, comfortable saloon to go with it)!

Really glad to hear it worked for you. I have a line on a few wrecking yards that have XJRs in them. So, I will go that route.

Can you please confirm if the new/used part, that you put in, had this number on the exterior, 2W93-9AA12-BE? If not, what is the one that worked for you?

Thanks again!

 

Burt,

the module I bought on Ebay was labeled '2W93-9AA12-BD' while the original module was labeled '2W93-9AA12-BA'.
I can only speculate but I guess the last letter indicates the version(?) of the otherwise same build. So these (BA-BZ?) should be compatible.

Btw, another Jaguar dealer told me that a new module has to be recalibrated. There is an option in IDS for this - if IDS recognizes the module (which my IDS-Version doesn't).
I'm only mentioning it cause the guy said this would be important. OTOH this was 'third-hand-experience' for him so it might be another 'urban myth' about our cars.
No offense toward Jag-dealers - but most of them don't know nothin' about these early ACC-modules.

Good luck!

 

Hi Ekki,

Thanks. That is really helpful. I just bought a 2W93-9AA12-BE on Ebay. Should have it on the car next week sometime.

Did you simply plug the BD model into your car and have it work, or did you need to take it into the dealer for CAN-bus programming before the car would work with it?

 

Burt,

great news!

I simply replaced the module. Btw, to get best access to the module you need to detach the hood support struts and then use a bolt for the front hinge which enables the hood to stay open in a 90 degree angle.
AFAIR there is a TSB/how-to here (can't remember where - in this thread maybe) but actually it's pretty self-explanatory.

Good luck - and let us know how it turned out.

Ekki

 

Quick note of follow-up for anyone who stumbles across this thread. I swapped in the BE module (my 2004 XJR had a BC module in it), powered up the car, and found no warning lights!!!

Big relief, and a very happy $2,900 savings over the dealer quoted repair. I haven't road tested it yet, but will on Sunday with a 300 mile trip to San Fran. Hopefully that will be uneventful. I'll report back if there are any issues.

-Burt

 

Hi thxalot,
I've been quiet(!) but watching the thread as I have the same issue. This is great news. Looking forward to your report on the road test! My original module was a BA. When I bought the car, the guy had tried to fit a module BD (2nd hand) but it still didn't work. I got the error "radar level out of range" which BBA Reman could not fix, so I suspect the module was just faulty. BBA Reman said it was a mechanical fault! I would like to try fitting another so your news is encouraging... just need to get one at the right price!!
David.