BCM problems-STEALERSHIP TRYING TO BANKRUPT ME!

[GRACAR]

JEEP 2002 Cherokee (Liberty) 2.5 CRD. No Lights, screen wipers, speedometer reading, remote door locking, rear door remains locked.

The Jeep is used as a second car, therefore used occasionally. About a week after the repair shop had fitted a new front drive oil seal we took the Jeep out and everything was working as normal, it then started to rain heavily, switched on screen wipers: Not working, tried side and headlights: Not working, but can still flash high beam, NB. as it was summer we hadn't needed to use lights and wipers for some weeks, speedometer: Not working but occasional sporadic movement to stick at reading 60 mph then drops back to 0 mph. Remote door locks: Not working, rear door and glass opening: Not working, cannot open even with key. Electric windows working fine. I have disconnected and re-connected the New battery, everything worked fine for 10 mins then reverted back to the same problems. I have checked fuses all seem OK.

Dealership ('Stealership') have run diagnostics and suggested replacing BCM and Junction Block which MAY SORT THE PROBLEMS BUT NO GUARANTEE and would cost over £2000, if problem not sorted they would just replace the sensors one by one, until either I RAN OUT OF FUNDS OR THEY FIXED THE PROBLEM.http://www.jeepkj.com/forum/images/smilies/wtf2.gif

I have read somewhere that there is a way to check sensors, BCM outputs, inputs with a Multi meter, is this correct? If yes, please give details. Your suggestions on how to check and rectify these faults is sort, please.
Thank you.

Graham

 

[Billwill]

JEEP 2002 Cherokee (Liberty) 2.5 CRD. No Lights, screen wipers, speedometer reading, remote door locking, rear door remains locked.

The Jeep is used as a second car, therefore used occasionally. About a week after the repair shop had fitted a new front drive oil seal we took the Jeep out and everything was working as normal, it then started to rain heavily, switched on screen wipers: Not working, tried side and headlights: Not working, but can still flash high beam, NB. as it was summer we hadn't needed to use lights and wipers for some weeks, speedometer: Not working but occasional sporadic movement to stick at reading 60 mph then drops back to 0 mph. Remote door locks: Not working, rear door and glass opening: Not working, cannot open even with key. Electric windows working fine. I have disconnected and re-connected the New battery, everything worked fine for 10 mins then reverted back to the same problems. I have checked fuses all seem OK.

Dealership ('Stealership') have run diagnostics and suggested replacing BCM and Junction Block which MAY SORT THE PROBLEMS BUT NO GUARANTEE and would cost over £2000, if problem not sorted they would just replace the sensors one by one, until either I RAN OUT OF FUNDS OR THEY FIXED THE PROBLEM.http://www.jeepkj.com/forum/images/smilies/wtf2.gif

I have read somewhere that there is a way to check sensors, BCM outputs, inputs with a Multi meter, is this correct? If yes, please give details. Your suggestions on how to check and rectify these faults is sort, please.
Thank you.

Graham

The Junction Block is basically the interior fuse panel...not much can go wrong with it. The BCM plugs onto the Junction Block and is the most likely cause of your problems.....the remote locking module plugs onto the BCM...it is about the size of a cigarrete pack.

I would suggest that you disconnect the battery, pull out the BCM from the rear of the Junction Block, re-plug the remote locking module on the BCM, put back the BCM and re-plug all the connectors going to the BCM/Junction Block.
The BCM is basically shown as a "black box" in the circuit diagrams...it is really just a chunk of memory with firmware running around inside...it may just need re-programming at the Dealership.

Try find a used BCM from a Breaker yard..2002 to 2004 should work although you may need to program some facilities into the new one.

You can download the 2002 Service Manual here...includes the circuit diagrams...about 42 MB in total. Use the circuit diagrams to measure the presence of the various voltages and grounds on the BCM...maybe a voltage or ground has gone missing. Other than that you need to be pretty proficient in Electronics to fault-find BCM issues.

Have a good look for wet connectors....there are some under the inside carpets and so check for wet carpets. Also check that rodents have not chewed through the wiring anywhere. The circuit diagrams will show you the locations of all the connectors.....you probably got some wet in the rain.
There are several connectors in the engine bay, drivers side (RHD), next to the air filter up against the right fender....take these apart...with some difficulty... and run a hairdryer over them....do the same with the connectors on the ECM on the left fender...after first dis-connecting the battery.

The Service Manual for the 2002 KJ is here...I would also advise you to download the section "2.5_2.8 Export Diesel"....covers the engine/gearbox etc. for our Export CRDs which are quite different to the USA 2005/6 CRD models.

Index of /manuals/Jeep/KJ

Once you have the circuit diagrams I can try to guide you through them....I had to fix about 6 wiring problems on my 2002 Export CRD.:emotions34:

 

[profdlp]

Just a word of encouragement, but Billwill has helped a bunch of people here (and elsewhere) with their electrical/electronics problems. You are in good hands.

 

[GRACAR]

Thanks for useful assistance.

Hi,
Thank you Billwill for the very useful info and links. I will examine the wiring diagram and get back with any queries/questions, if I may?

profdlp Thanks for your encouragement, there is hope!

Thanks again.http://www.jeepkj.com/forum/images/smilies/waytogo.gif:waytog:o

Graham

 

[GBKJ2003]

Hello there. Check the earthing points where the dash bolts to the body work they are behind the panel over the foot well they are on both sides of the dash. Also there is one below the battery holder behind the headlight. This does get corroded. I had a problem there and drilled it out , re crimped the cables used a brass nut and bolt. Tighten them up covered in galvanised paint on both sides and not had any problems since. Hope this helps.

 

[bluedanube]

Thank you

I have the same problem going on! nervous.gif I will follow all these useful advices

 

[profdlp]

Good luck, bluedanube.

 

[twowings]

"I have disconnected and re-connected the New battery"

New does NOT always equal GOOD...be sure the battery and its connection are indeed doing their job...