Chrysler Repair: van power door locks, power door locks, positive temperature coefficient

Question
QUESTION: I have a 1999 town & country - having problems with door locks - inside door lock switch stopped working, will not lock or unlock doors - remote worked on unlock not lock for a short time and then stopped working on unlock also - when remote is used the lights flash for unlock and lock as programned - I can hear the relay under hood clicking (light relay?) - I tried disconnecting and reconnecting the battery and that did not change anything - this all started after the van sat a while and the battery went dead - I had to use the key to manualy unlock the door - I then charged the battery and these problems started - Any idea's - Thanx

ANSWER: Hi Ray,
The power for the door lock motors is the "fuse" (positive temperature coefficient type) located in position #3 in the row of 10 sockets located just below the four plugs of the fuse box located under the dash. So see if that is blown. The system is mediated thru the body control module which is located on the back side of the fuse block. One possibility is that some water leaked in around the lower corner of the windshield that can temporarily disable of introduce "gremlins" into the operation. As long as the lights flash and other interior courtesy lights work the fuse that operates when the van if "off" is ok (#28 in the underhood box). So that PTC of a body module malfunction is the probable cause. I would not be too upset about this situation because other problems with this system can be much worse: theft control system issues that lock you out of starting the motor, for example.
Roland

---------- FOLLOW-UP ----------

QUESTION: Thanx - after I sent this the unlock started working on the remote again - not the lock just unlock - the switch on the door still does not work for unlock or lock - Something else happened - when the fuel gage got below about 1/2 it started going down real fast - low fuel light went on and the readout in overhead counsel said I only had a couple miles to go to empty - when I filled the tank it only took about 7 gallons and the gage showed full again - this has happen 3 times now - Could all this be related and pointing to the same problem? - I am a little worried what will happen next - everything else including intior lights are working as of now - Thanx

Answer
Hi Ray,
The malfuntion of the fuel gauge along with that of the door locks makes me suspicious of the body control module having some sort of water perhaps on the 40-pin plug that has pins number 41-80. The wires that are involved with the door locks and the fuel gauge are in the area around the middle of the plug (pin 46 for the gauge and 45/55 for the door locks). If you have some foreign substance grounding out those pins, that would produce the kinds of misbehavior you are experiencing.
Again, do you see any coincidence of the problems with some heavy rains or van washing that might have caused some water intrusion at the left lower corner of the windshield which is directly overhead of the that unit and its plugs?
Roland