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HiddenTalent 08-13-2011 05:29 PM

Need Help Solving 2 DTC's... SOLVED... I can't make this up!
Hi guys,

have 2 DTC's that are getting real annoying real fast...

U0415 - Invalid Date Received From Anti-Lock Brake System Control Module
C107C - Brake Pedal Switch Half Stuck

I noticed that these came on after I had the wheels rotated at a local shop. I've checked all connections I can find.

I've also done a lot of reading/searching on this code and the majority say to reflash it, which doesn't make sense to me. I'm looking for a solid answer...

Any help is appreciated.

robpp 08-13-2011 07:36 PM

Re: Need Help Solving 2 DTC's...

When Monitored:
With the ignition on, but not during first run.

Set Condition:
When the Anti-Lock Brake Module detects a mismatch between the two signals of the redundant stop lamp switch.

Possible Causes







I cant find the other one in my service manual?

since the second one is communication. I would think the switch is not doing the CORRECT thing.

HiddenTalent 08-15-2011 01:06 AM

Re: Need Help Solving 2 DTC's...
Thanks Rob!

It's damn near impossible to find some information on these codes... Since they come on together, I'm wondering if one is causing the other... I'll have to look again at the order they readout in and maybe if I can kill one then the other dies too. If a ABS sensor is getting mixed signal, maybe it is because it's not good! Makes sense to me!

Where are these sensors? How much do they cost?


Edit: Electronic Brake Control Relay could be sticking? Possible?! It's under ten bucks!

Also, looks like the wheel speed sensors are repaceable, only ever replaced wheel bearings with sensors built in, but seems to be replaceable for us pretty cheap... ???

viking757 08-15-2011 01:27 AM

Re: Need Help Solving 2 DTC's...
1 Attachment(s)
If you check the attached screen shot one is definitely causing the other. Since you also have a code for your brake switch and one of the set conditions for the U0415 DTC is the FDCM recieving implausible data for brake switch status. My guess would be to investigate the other problem then whatever is causing it is also making the U0415 come up.

HiddenTalent 08-23-2011 12:12 PM

Re: Need Help Solving 2 DTC's...
Bump with info...

My buddy was driving behind me the other day and my codes had just come on (they come on randomly). He said my third brake light was on, but I wasn't on my brakes.

This makes me think one of the relays is sticking.

Here's my $40 plan.

First replace the brake light switch and the brake light relay ($15), then I'll do the high mounted brake light relay ($6), and finally the electronic brake control relay ($6). All said and done for $40 or less. See if it works. It is better than dealer costs for nothing!

2005JGC 08-23-2011 01:36 PM

Re: Need Help Solving 2 DTC's...
I really dont know all the details about the system, but I would half was suspect that your 3rd brake lamp is coming on as a "stupid state" because it cannot trust the brake switch signal it may turn on the 3rd brake lamp to warn other drivers. Much like if you disconnect the cluster that relays your headlamp switch input, wiper switch input... when disconnected your wipers and headlamps turn on because its safer they run in the middle of a 100 degree day than not running in the rain at night.

My first suspect would be the brake switch... again suspect. Most lamp circuits are not monitored (I know in some rams they are) but typically they are not EVEN THEN, they dont monitor that they turn on they monitor if their is continuity aka a functional bulb... so I would lean away from a sticking relay at this time. So long as the FCM is not commanding the relay be closed its happy reguardless of if the other side of the relay is still flowing power.

HiddenTalent 08-30-2011 11:49 AM

Re: Need Help Solving 2 DTC's...
I can't make this stuff up!!

Around when I posted this thread, I was driving with my buddy behindme, had turned on my fog lights and just about 2 minutes later the light came on. At the time I made no connection between the fog lights and the lights.

I got a call from him almost immediately saying that my third brake light was on, with one of the bulbs burned out. He also said that when I was hitting the brakes my right rear brake light was not working.

I acknowledged that and intended on replacing it, which I already had a bulb in my tool chest. The next day I replaced the brake switch, $10, with no success. I went to work and my mechanic was picking up the Jeep to do a trans fluid, oil, and rear diff fluid change before a weekend trip (I also have owned the Jeep for a year and never changed any of that, so it made sense).

When he dropped it off, he mentioned the brake light issues. When I was leaving for my trip I had grabbed my bulb and a torx set. I was in a bit of a rush so I just threw it in the Jeep and was going to do it later. Well, on the trip I stopped at a rest area and decided to change the tail light bulb.

VOILA!! No more service 4wd system lights!


Like I said, I can't make this crap up!

IlanLCD 12-18-2014 11:44 AM

Re: Need Help Solving 2 DTC's...
Bumping this old message, as its just helped a friend mine after three garages didn't find the matter when he was getting those codes.

Eventually it was only a burnt brake light that was shortening with the main light current.

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