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-   -   Pcm? (http://www.jeepgarage.org/f5/pcm-29787.html)

chance 10-16-2011 11:58 PM

FCM? PCM? Help please.
 
So, I have had a high beam that does not work and I have checked the bulb to see if that was the issue, it isn't. =\

So I was wondering has anyone ever had this issue and if it is indeed the PCM?

How would I get this fixed?

Thanks guys!

2005JGC 10-17-2011 12:33 AM

Not the pcm but I have seen low beams on a pt cruiser not work due to a faulty driver in the front control module.... Its possible.

Sent from my SCH-I500 using Tapatalk

chance 10-17-2011 01:33 AM

Re: Pcm?
 
Quote:

Originally Posted by 2005JGC (Post 499783)
Not the pcm but I have seen low beams on a pt cruiser not work due to a faulty driver in the front control module.... Its possible.

Sent from my SCH-I500 using Tapatalk

How would one fix this?

chance 10-17-2011 12:20 PM

Re: Pcm?
 
Well, I called the dealer and they told me that I basically need to make an appointment to get it checked out.

So that's one hour of labor which is 80 dollars...Would that be worth it?

I mean I just don't want to do it if I can fix the issue on my own.

robpp 10-17-2011 12:42 PM

Re: Pcm?
 
the PART, if its the FCM, is about 300 . so 80 to confirm is prolly worth it. it the thing between the fuse box and the battery so unless it eneds to be programmed, i would NOT let them install unles its less than like 50 bux/

this may not be your exact one but its a good WK part number.

http://factorymoparparts.com/56040662ah.html

chance 10-18-2011 01:53 PM

Re: Pcm?
 
Thank Rob!

Would they be able to tell me my part number when they diagnose it?

Would they be able to tell if it just needs reprogrammed? or will they just tell me I need it replaced?

robpp 10-18-2011 03:23 PM

Re: Pcm?
 
that i cant answer bro....maybe Andrew can????

2005JGC 10-23-2011 03:30 PM

Re: Pcm?
 
You *should* be able to get the part number by calling a parts department with the last 8 characters in your vin and they can give you the part number.

It likely wont be a reprogram to resolve the issue, sometimes modules freak out and a reset will bring it back to life, but not very often. It will likely need to be replaced.

I havent even looked at a wiring diagram and have to run, ill look today and get back to you with some possibilities.

chance 10-23-2011 07:44 PM

Re: Pcm?
 
Quote:

Originally Posted by 2005JGC (Post 502809)
You *should* be able to get the part number by calling a parts department with the last 8 characters in your vin and they can give you the part number.

It likely wont be a reprogram to resolve the issue, sometimes modules freak out and a reset will bring it back to life, but not very often. It will likely need to be replaced.

I havent even looked at a wiring diagram and have to run, ill look today and get back to you with some possibilities.

Thanks Man, just let me know!

2005JGC 10-23-2011 08:13 PM

Re: Pcm?
 
the high beam drivers are C2 pin 12 and pin 7 in the front control module (white/gray and white and dark green respectively). Pin 12 is for the Right high beam output and pin 7 is for the Left high beam output.

If you verify the wire integrity to the best of your ability (check continuity from the pin at the FCM to the bulb socket, make sure there is not an obvious short to ground or power, then at the fcm turn the high beams on and probe in to the back of the connector while plugged in to see if it puts power out.

If you dont have power and have done what you can to verify circuit integrity (obviously seeing every last inch of the wire is boarderline impossible without massive amounts of time), so the aforementioned checks will give you a very good idea of circuit integrity.

It was a driver just like this that I have seen fail in a pt cruiser.

Know that I have seen the wire harness down by the frame rail rub on things and cause some shorts (below the battery).

If you replace the FCM, I dont think there is anything that needs to be programmed... I cannot remember, not something I comitted to memory as I like to hook the scantool up no matter what I replace and verify all is good. also make sure to plug in the OCM fuse (typically in a plastic cover not engaged in the fcm)... if you start your rig and your airbag light is on insert fuse here ;)

fatfreddy 10-23-2011 11:20 PM

Re: FCM? PCM? Help please.
 
Quote:

Originally Posted by chance (Post 499775)
So, I have had a high beam that does not work and I have checked the bulb to see if that was the issue, it isn't. =\

So I was wondering has anyone ever had this issue and if it is indeed the PCM?

How would I get this fixed?

Thanks guys!

Check your hi-beam relays.

2005JGC 10-24-2011 01:39 AM

Re: Pcm?
 
According to service information (wiring diagrams and owners manuals were both consulted), the high beams are not relay controlled. There is a high side driver in the FCM that drives them. Not only does it not show one on the wiring diagram, but consider this last week I had a blower motor intermittantly inop in a wk and looking through my diagrams it clearly showed a relay, furthermore service information AND the owners manual lists a relay for the blower motor in the pdc (space 29 i believe)... THERE IS NO 29! furthermore the issue was in the junction block with the ign run output relay, another relay clearly listed in service information but it is non servicable individually... It was awesome deciphering the miscommunication between the guy that knew what to type and the guy writing the information... All of that to say service information isnt 100% but according to both 06wk service info and 08wk service info there are no relays.


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