Odd Dashboard Cluster and Control Behavior

Question

Car: 2005 Dodge Grand Caravan

Problematic behavior

About this time last year is when this all started. It first surfaced in that when I went to startup the car it started but after about a second it stopped. A few times doing this, it finally stays running. But this is typically the start to a 2 - 5 day odd-symptom period, including the following behavior:

• while driving the speedometer gets stuff at a certain speed
• while driving the cluster indicators can go haywire (i.e. oil pressure says its erroring, airbags indicator blinks, gas gauge goes to empty when its not, etc. basically all of the cluster gauges have mis-reads)
• when I stop the car and take the key out (and even open the door) the radio and the cluster stay "on"

This happens, like I said, for 2 - 5 days and then it goes back to normal after this period. I tried taking it to a mechanic but by the time he looked at it, it went back to the "normal" state and there was nothing to diagnose.

I read the error code (which also goes away when returning back to "normal") and it was a communication error with the cluster control module (I think that's what it is called).

Then yesterday morning, all was just fine. Drove the car in the morning. In the afternoon, I noticed that the dome lights were on and the door ajar indicator was showing an open door (this was new behavior). I turned the ignition on and then off. That behavior went away. Then last night I noticed the dome lights and door ajar were again on. Same thing, I turned ignition on then off and it went away. Sure enough, woke up to a dead battery.

Funny thing: it didn't happen all summer long during the warm months. Not sure if this is related to temperature

Any ideas here? Does it sound like the module itself is just slowly failing?

Answer 1

As I was reading this, 'Rain' came to mind. Water ingress could definitely cause problems like this. Could you match the problem up to rain even a day or so before. I have seen water get in a car, which then slowly creeps along inside the wire insulation and then ends up at an ECU, causing all sorts of problems. Checking the ECU connectors would likely show up the problem where green corrosion of the terminals will likely be seen and maybe water. Before finding where the water got in, I cleaned the ECU connector, then packed the connector with petroleum jelly which stopped the water getting into the connector. The symptoms I had were very similar, the alarm would go off, the lights would be illuminated on the dashboard, the interior light would be on and I would not be able to lock the doors.