Hi all,

Since I bought mine 2006 Limited CRD in 2016, I am having continuous issues with the constellation of [ABS - ESP/BAS - Slippery Road] lights turning and and off with and without apparent reason. Some such instances were caused by a broken wire from one of the speed sensors, which I fixed by properly soldering and waterproofing the joint. Some were similarly caused by salt water coming inside old poorly insulated twisted wire joints, which I repaired in the same way. It still keeps happening. The latest scenario was "slippery road" light flashing on the dash and brakes applied to some wheels on a perfectly dry pavement. Finally got myself and OBDII scanner capable of reading my ABS codes. The code said poor left rear speed sensor. Replaced the sensor, now all the three yellow lights are permanently on with codes reading C1020 - left rear speed sensor circuit. I would have ignored all that nonsense, but the darn thing won't let me use cruise control unless she is totally happy with zero yellow lights on.

But now I am starting to suspect something different. Yes, I still may have one of those notoriously brittle speed sensor wires broken, sure thing. I may have a faulty ABS control module (or how is it called in Chrysler lingo?). But why sometimes my red parking brake light comes on together with three [ABS..] yellow lights? How likely is it that ABS module also controls the parking brake light? The latter is usually directly connected to some mechanical switch under the parking brake lever (though modern engineers surely may find some totally twisted reason to hook it up to every other piece of electronics in the vehicle). But now according to this, admittedly not 100% trustworthy account,

https://www.justanswer.com/jeep/75uf2-j ... brake.html

very similar symptoms (including red BRAKE light!) were the result of faulty BCM (Body Control Module). Now I am starting to recall that I had some intermittent issues with operating my door locks with remote and had to use the key instead. Also at some point I started to receive intermittent warnings to "check the TPMS system". Both issue are gone for now, but it is my understanding that those might be directly related to BCM, correct? And it does makes sense that the dash BRAKE light is under BCM control. In fact, according to this, relatively recent report,

https://www.jeepforum.com/forum/f28/200 ... f-4011729/

a bunch of electrical issues, (including darned dash BRAKE light!) got fixed by supplying the proper ground to BCM.

Anyhow, was anyone able to fix yellow [ABS...] lights by fixing/replacing the BCM? Any other hints are also appreciated.

Thanks in advance,
Alex

_________________
2006 Liberty CRD Limited, GDE ECO tune, Provent 200, 2-stage Weeks kit, ARP studs,
Aussie fan shroud, Trans drain plug

ESP/BAS problems can be caused by a bad clock spring as the exact angle of the steering wheel is read out.
Cruise Control is also affected by a bad clock spring.

Where are you located? LHD 2006 CRDs have a known problem of the wire harness behind the Fuel Filter Head Mounting Bracket being getting the wires fraying to chassis behind the bracket.

I have seen lots of reports of bad "new" wheel sensors being fitted and certain makes of wheel bearings causing ABS problems.

The wire harness runs around the whole engine bay passing through several connectors on its way which may have some bad contacts or fraying to chassis.

Or could be a bad BCM...maybe try one from a Breaker Yard...you can get some functions re-programmed later!

Have you pulled any Codes out?

_________________
2002 Export CRD

Hi Billybob, thanks for the response and suggestions! I am in Indiana, USA if that makes any difference I recall reading about the harness behind the fuel filter, thanks for the reminder! BCM is rather hard to find these days. I found some here

https://automotix.net/usedautoparts/200 ... seq_num=15

but for some weird reason they are all listed as being installed on the passenger side - maybe they were installed in left side driving vehicles, like ones from UK or South Africa?

Thanks again!
Alex

_________________
2006 Liberty CRD Limited, GDE ECO tune, Provent 200, 2-stage Weeks kit, ARP studs,
Aussie fan shroud, Trans drain plug

The BCM is definitely bolted on the rear of the internal fuse panel, Junction Block, which on my Jeep is on the Right side ie. the Driver Side in my RHD 2002 Export CRD.

I was just not sure if you were in the USA or somewhere else because as far as I know the issue with the 2006 CRD Fuel Filter Mounting Bracket causing damage only applies to LHD 2006 CRDs.

Some time back I advised a British owner of a 2006 CRD to check this mounting bracket and he did so and stated that here are absolutely no wires located there!

_________________
2002 Export CRD

Does your scanner read data from the ABS module? If so I would recommend you drive around and look at the data from each wheel sensor, ideally you will see that one is not reading or one is not reading correct.


The BCM in attached to the fuse box, which follows the drivers side of the vehicle.

_________________
http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Thanks for pitching in Sir Yes, I finally found an affordable OBDII reader, Innova 3020 that can read my ABS codes (went through several of those stating they could do ABS, but failed on my CRD) . I got bunch of codes loosely suggesting left rear sensor was bad, replaced the sensor and started getting "C1020, left rear sensor circuit". Just didn't want to bore the crowd posting all the codes here. I am still going through testing the wiring, just thought that due to the stupid parking break light coming up, BSM might be involved.

As for the wiring I am trying to go through this procedure:

http://liberty.eurekaboy.com/abstest.htm

Didn't work, until I realized the controller I have been looking at was not an ABS module ))

You live for hundred years, you learn for hundred years, you still die a fool (Russian proverb)

Cheers,
Alex

_________________
2006 Liberty CRD Limited, GDE ECO tune, Provent 200, 2-stage Weeks kit, ARP studs,
Aussie fan shroud, Trans drain plug

Quick question: do the wheel ABS speed sensors on 2006 CRD use polarized connection? That is, does it matter which wire connects to which terminal on the sensor? Sensor connectors are polarized and the two connection wires are color coded differently. However it is hard to believe that these type of sensors will somehow operate differently if connected in reverse - or am I missing something?

Thanks in advance,
Alex

_________________
2006 Liberty CRD Limited, GDE ECO tune, Provent 200, 2-stage Weeks kit, ARP studs,
Aussie fan shroud, Trans drain plug

OK, all is well that ends well! Got really p&$$@d, ripped all the rear speed sensor wires off my 06 CRD and sure enough the one connected to the left wheel sensor had a hidden break! I didn't even bother to locate it, because even under the close inspection the wire looked normal (no kinks, etc.). Got a set of really flexible multi-strand wires with silicone insulation as a replacement, put them into makeshift "conduits" made from thick wall tygon (or was it polyurethane?) hoses, attached those at several points and verified that movement of the suspension will only bend them slightly without pulling or chaffing. Insulated the hose ends with self-sealing silicone tape to make sure no moisture can get in. Finally no yellow lights on the dash, cruise is back to work, fingers crossed!

Cheers,
Alex

_________________
2006 Liberty CRD Limited, GDE ECO tune, Provent 200, 2-stage Weeks kit, ARP studs,
Aussie fan shroud, Trans drain plug

Great! Well done for fixing the elusive breaks in the ABS wheel sensors.

_________________
2002 Export CRD