- #1
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- 66
I drive a '99 Chrysler 300m. Recently on an hour long freeway trip the interior lights were randomly turning on, then after a random time from a few secs to minutes they would turn off. At first I thought a door ajar sensor was flaky, but then realized that the dash display did not show a door open.
I was not real concerned with this behavior until one morning I found a dead battery. Could be a lot of things, so I jumped started the car and went about my business. Next morning same thing, now I had problem. I reasoned that those blinking lights might be the source of my problem. Chilton's pointed me at the fuse for the interior lights, each night I pulled that fuse and sure enough no more battery problems. I also learned that all of these functions were controlled by the BCM (Body Control Module). Apparently it was getting a bad signal or was spontaneously producing one.
I checked some Chrysler forums and found others discussing similar problems. The most common fix was usually something to do with a bad ground. In the forums I also discovered that the trunk light was also controlled by the BCM. When we first bought the car (used) the trunk light did not work. I found a severed wire in the bundle at the flex point. I repaired that and the trunk light has worked fine since. Figuring that if it was a trouble once it might be again I reopened the bundle and inspected the wires for anything that might cause troubles. I found nothing of interest except that at one of my solder joints the end a single strand of copper was poking through the shrink wrap by something less then a mm. I did not see how that could cause a problem as there was nothing for it to touch. In any case I carefully wrapped it in several layers of black tape then re-taped the bundle and attempted to ease a bend near the trunk hinge bracket.
Well even though I really do not feel I fixed anything the lights have quit blinking. I have taken several signigant drives and it has not recurred. I have not been pulling the fuse and have had no further battery problems.
Is there anyone here that knows something about the operation of the BCM in this sort of car. Could it be that this is really fixed or is it just intermittent and waiting spontaneously fail again?
I was not real concerned with this behavior until one morning I found a dead battery. Could be a lot of things, so I jumped started the car and went about my business. Next morning same thing, now I had problem. I reasoned that those blinking lights might be the source of my problem. Chilton's pointed me at the fuse for the interior lights, each night I pulled that fuse and sure enough no more battery problems. I also learned that all of these functions were controlled by the BCM (Body Control Module). Apparently it was getting a bad signal or was spontaneously producing one.
I checked some Chrysler forums and found others discussing similar problems. The most common fix was usually something to do with a bad ground. In the forums I also discovered that the trunk light was also controlled by the BCM. When we first bought the car (used) the trunk light did not work. I found a severed wire in the bundle at the flex point. I repaired that and the trunk light has worked fine since. Figuring that if it was a trouble once it might be again I reopened the bundle and inspected the wires for anything that might cause troubles. I found nothing of interest except that at one of my solder joints the end a single strand of copper was poking through the shrink wrap by something less then a mm. I did not see how that could cause a problem as there was nothing for it to touch. In any case I carefully wrapped it in several layers of black tape then re-taped the bundle and attempted to ease a bend near the trunk hinge bracket.
Well even though I really do not feel I fixed anything the lights have quit blinking. I have taken several signigant drives and it has not recurred. I have not been pulling the fuse and have had no further battery problems.
Is there anyone here that knows something about the operation of the BCM in this sort of car. Could it be that this is really fixed or is it just intermittent and waiting spontaneously fail again?