I have an '08 1500 Hemi that is currently at the dealership for a repair that was prompted by the AC not cooling properly sometimes. I took the truck in for service at CarMax (where I purchased it, and where it is still under warranty) and they determined that "a control module" had gone bad and was causing the AC condenser fan to run constantly, instead of cycling on and off. So, they installed a new module (I am assuming it's the FCM, but have not been told that specifically), but then discovered the vehicle would not run at all. I was then told they had to send the truck to the dealer to have the module programmed. I should hopefully get it back tomorrow, but in the meantime, I'm wondering if the FCM may be related to some other issues/things I've noticed:

-The truck has cut off on me while driving, once while driving at low speed after hitting a large pothole that was submerged under water, and once while decelerating to a stop

-The headlights dim and HVAC motor speed slows when any of the power window switches are depressed, and system voltage drops ~0.5-0.75 volts

-The truck will occasionally run sluggishly, and will then magically start running better and have more pep for several days

-The MDS seems to be slow to disengage at times, particularly when accelerating up an incline from a stopped position. Sometimes under these conditions, I have to stomp on the accelerator pedal to get MDS to turn off, and then the truck will take off like a rocket, which is rather dangerous.



Is there any chance all of this is related to a bad FCM?

Thanks in advance for any help.

 

Passenger side low beam problems have haunted me for years on this truck. 1st time it was the fuse box. Changed it and that solved the problem for a couple years. Then it was the FCM. Changed it and it soved it for a couple years. Now the problem is back again just in time for state inspections.

 

IM HAVING the SAME issue!!! were you able to figure out what the problem is?

 

Sorry to hear about all you've been through! :-( Try eBay. There are usually parts available there. I saw a PCM for my 2003 Caravan SE available for $150. The part will be probably be used, though.

 

Just dealt with this issue. The PDC has a printed circuit board that the fuses and wire looms plug into as well and the FCM plugs in on the end. The relay that energizes the parking lights and rear running lights is triggered from the lower pin of the sixth pin from the right. The printed circuit board completes that circuit using a tracing that runs close to the FCM plug so it was corroded and broken by exposure to atmospheric conditions. Soldering a wire to complete the route repaired the problem. A coating of silicon was applied to prevent future corrosion of the other traces on the circuit board.

 

Is the PDC and a TIPM the same thing? My drivers side headlight is out and the dealership wants $900.00 for the part...

 

There are bad euphemisms for that kind of treatment. There is one 13mm body bolt holding the unit and one plastic quick screw. Then the unit can be shifted toward the engine 1/2" and brought up. The metal device on the side is retained by four 1/4" head screws. Take them out and remove the unit. Spray everything with electrical cleaner then replug the device. Try the lights.

 

I've been chasing the headlight/tailight FCM/PDC problem for a while now. On my '03 Ram 1500, I first opened the PDC to look at the circuit board for corrosion but it was only dusty, all the tracers looked solid from beginning to end.
My problem is random at best, sometimes I have lights, sometimes I don't. I recently bought a replacement FCM because I though for sure this was the problem. Turned out I was wrong. With the original FCM (even after cleaning the male prongs), I have the right front low beam and NOTHING else(except the "center high mounted brake light") and I mean Nothing: no high beams, tail lights, rear brake lights, turn signals, windhshield wipers, horn, hazards, etc. nothing.
The replacement FCM appeared to work, but I took it to town the other night, about 4 minutes down the road, and I turned on the left turn signal and POOF! ALL exterior lights went out along with horn, hazards, wipers. Did I get a defective FCM or is it the PDC? Maybe something else like the male-to-female connection on the FCM-PDC (or something else - multifunction switch, headlamp switch)?
I have also cleaned all the connections underneath the PDC, cleaned all the dirt off, did some voltage tests on the headlights when they work, outputs volts are good.
Not sure what to do next.

 

I'm having a similar problem on the 02 I just bought. I pulled the PDC and took the top off and that gave me access to the bottom of the circuit board. How did you get to the top?

I have a feeling I'm gonna have to trace my grounds but if you could give me a pointer on getting to the top of the circuit board I'd appreciate it. All of my electronics are "AE" code and apparently don't exist.

 

Just "looking" at the PDC printed circuit board tracks does not tell you 100% that there is continuity.
You really need to work through the circuit diagrams and check out those circuit board tracks using a good multi meter and check for open circuits or even high resistance as that can be just as bad as an open circuit.
I changed out my PDC for a new one well over 6 or 8 years ago due to the famous park light/side light issues.
Never had a problem since.
Al.