Chrysler Repair/2000 Intrepid, Random Door Locks-Odometer Flashing-No A/C cooling-No engine cooling fans
QUESTION: 2000 Dodge Intrepid
Problem started 2 years ago, parked car in shade, north side of shop, cool and damp, 3 months later upon driving it, door locks randomly lock, un-lock, at any time, parked or driving, engine running or not, key in or out.
Odometer and trip meter flash unreadable and sometimes readable numbers, occasionally speedometer and tach needles will jerk around and sometimes sit at zero periodically.
Engine cooling fans do not operate, noticed this last summer when car was idling and over heated.(I tested fans by jumping relay terminal and fans operate).
I have a service manual and have spent many hours meticulously testing grounds, corroded/misaligned connections, faulty/bad wiring.
I removed ECU and was going to send it in for a core and get a used one but I am not satisfied 100% yet that that is the problem. I need to be sure..
I also removed the back cover of the ECU and noticed their is a small (1/4") tear in the sealing material, and at that area, the circuit board looks to be darkened or slightly chard.(possibly moisture/condensation entered will being parked, not sure, but assume it is likely.
I would appreciate any other help you can give me, the only alternative is to jump the cooling fans to operate and drive 30 miles to a repair shop and have the ECU tested, unless it can be tested out of the vehicle.
ANSWER: Hi Tim,
Sorry for the delay in responding. I was off line for lack of a functioning computer.
As to your problems:
The fans: have you measured the resistance across the coolant temp sensor? It should be about 4,000 ohms when cold, and drop gradually to around 1,000 ohms when the engine reaches operating temperature.
On the door locks and the instrument cluster, both of those are mediated by the body control module so I would check fuses 7,14,16,18,19 to notice if any of them might have a subtle crack in its internal wire which causes it to spontaneously open then close when current flows.
The other possibility for the door locks is that one of the doors (most likely the driver door) is not firmly in the door frame which if so you could correct by moving the striker in the door frame a bit inboard so as to more tightly secure it. You might also monitor the voltage on fuse 1 which gets its supply the ignition switch and that section of the switch might be flakey, of fuse 1 might also have a subtle crack.
Let me know if any of these suggestions proves helpful.
Please read the PS below and respond to it.
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QUESTION: Thanks Roland, I will check everything that you stated, but it confuses me that all this would happen at the same time...I will do this today or tomorrow and keep you posted,,
ANSWER: You are welcome, Tim. I'll await a progress report.
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QUESTION: Hi Roland, found time today do do some troubleshooting on car.
Checked all fuses, especially the ones you mentioned, voltage at #1 fuse, ignition on only also with car running, it is always around 13.21-13.48v, I also wiggled, moved and tilted steering wheel and ignition key and seen no voltage change.
It takes about 10 minutes of car running before Odometer and trip meter start flashing, this time today, only the Odometer and trip meter flashed, door locks acted normal as did the cooling fan. (ohms where ok at sensor and fans came on as normal this time after engine running about 20 minutes.
A/C clutch/cooling still does not function, but heater fan and functions seem to be ok this time also...
Seems like the problem just like to come and go as it like to different areas, I did notice that when the odometer is flashing, when I open the doors, or turn anything on that changes the voltage very little, it changes the way and brightness acts on the Odometer and trip meter.
One more thing, if car is not running and key on, and Odometer and trip meter are not flashing, but are only blank, and I put 10amp charger on battery, it will cause the Odometer and trip meter to start the flashing...
Hope I'm not confusing you,,,
Thats all I have for you as of now..
We can only deal with what doesn't work currently. The AC compressor clutch will only be activated if the system has sufficient refrigerant in the system, so I would suggest that you verify that is the case by adding some to the system to see whether it then functions, or you can measure the voltage at pin 42 of the pcm which is the pressure transducer signal wire.
On the cluster, the readouts of the odo and trip meters seem to be voltage sensitive. The voltage supply to that part of the cluster is from fuse #1, and from fuse #7 (which is connected to the battery). So if both those fuses show steady voltages in the 14V range when the engine is running, then the only other possibility is that one or the other of the ground wires is loose. There is a black wire, and a black/green wire which are grounded side by side with a number of other ground wires under the dash on the left lower edge of the center stack so try to find that common ground and check it for tightness/corrosion. If the voltages and grounds are good then the digital cluster sections for those to readouts may be flakey.
I would appreciate your doing a 'thank/rate' of me if you believe I deserve that.