Dodge Repair: 03 Neon: RKE wont lock the doors

Question
QUESTION: Hi!

I have 2003 Dodge Neon, and I just noticed that keyless entry remote only unlocks doors. I bought the car recently and I have no idea what has happened. Same thing happens when I use my key to lock, I know it should lock by turning (on drivers side) clockwise and unlock counter-clockwise. Remote unlocks doors from both lock and unlock buttons. Both door switches work as they should.

I have tried replacing RKE module and it didn't help.

ANSWER: Hi Jaakko,
I find nothing in the wiring diagrams to explain this problem. There is one possibility, a feature called "door lock inhibit" which prevents the RKE from locking the doors. That is when both the key is inserted in the ignition switch and when the driver door is ajar/open.
My suggestion would be to move the driver door latch bar (located in the door frame) in-board a few millimeters so as to be certain that the door is tightly closed against the door frame. If that doesn't fix it, then it is possible that the switch which detects that the key is in the ignition switch socket fails to open when the key is removed so that is giving a false indication of the key being in the  switch.
That could be checked by removing the instrument cluster and measuring if the resistance to ground is infinite or zero ohms at pin 23 of the cluster plug when the key is removed. It should go back and forth when you insert and remove the key.
Roland          

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QUESTION: Key left on makes chime to warn and instument clusters door sign illuminates if drivers door is open and shuts off when closed. The lock and unlock with key in door started working by jiggling the connector to the lock cylinder.

This car has probably an aftermarket keyless entry system. I have successfully located the wires which are supposed to lock and unlock doors and they both go to pin 10 (Light green, no black stripe). If I remove one of them, unlock works as it should and lock makes this other unit to only blink turn signals as it would lock the doors, but not actually locking anything. I think there can be faulty wiring whith this, but I have no idea where the lock wire is supposed to go. I have tried light green wire with black stripe and door lock relay output with no success.

Answer
Hi Jaakko,
Actually there is only one wire from  each of the door lock/unlock cylinders. Instead of there being two wires the system uses two different value resistors to "ground" and the module detects which of the resistances to ground you have just connected momentarily. For some reason it is not 'seeing' the 'lock' resistance. So it could be a faulty system module.
Roland