Chrysler Repair: Starting ,electrical 93 Lebaron coupe GTC, bosch starter, powercenter

Question
QUESTION: Roland, I have 93 Lebaron with the Mitsubishi 3.0 engine and have difficulty with it starting. I replaced the bosch starter and it ran fine for about a week, until one day I started it followed by turning on the defrost. When I slid the blower control switch the headlights and instrument lights went out, then came back up, during this period the radio also lost its programming. I drove the car 3 miles when the headlights and instrument cluster darkened again,I

returned the vehicle home and turned it off.When I returned to check out the problem the vehicle would not start. I proceeded to disconnect the battery and troubleshoot the wiring to the starter and the blower switch and the powercenter under the hood, I was getting continuity to ground through the positive battery cable connector to the power center and proceeded to pull fuses until I got to the I.O.D. fuse this seemed to be the problem. After about 20 minutes I relaced the fuse reconnected power and low and behold it started and I believed the problem to be repaired, I was wrong. The next time I went to start the vehicle it wouldn't start the instrument cluster warning and check lights are very dim and go away completely when the brake pedal is depressed. The key in ignition bell rings intermittantly and twice there has been a high rate clicking sound coming from the vicinity of the body computer (what all does this monitor or control)? The vehicle has approximately 285K miles on it and up until now has been electrically sound. No codes other than 55 were indicated when I checked with the ignition switch. I am perplexed.
Today 7-25 I pulled what I believe to be the BCM (5x5 square,next to passenger right foot 2 multiprong connectors)I cleaned connectors and sockets with contact cleanerand reinstalled. The key in bell works now initially the cluster lamps came back up full, nothing else working. Dome light switch cause clicking from bcm, turn on headlamps sound coming from behind dash, cluster lights dim again.
Another oddity with this vehicle according to vin built 10-92 european (mfg usa bought usa)number label on bcm not traceable 84-2a31156, smaller label missing. Board inside box has same label and barcode with chrysler looking number printed on board 4632382 (suspect board pn. As stated above I'm at a loss.
Thanks for what help you may provide





ANSWER: Hi Tom,
I didn't quite understand your reference to the IOD fuse. I assume that you mean fuse 13. If you mean it seemed to be the source of the short to ground then I would suspect the BCM is the most likely problem. Try measuring the resistance that is shown by that fuse 13 to ground after you have unplugged the bcm. The internal courtesy lamps and cluster, and the radio memory are the only things other than the bcm that are powered by that fuse. The illumination of the cluster is also controlled by the bcm as well as a great many other body systems: door locks, windshield wiper, fuel gauge, key lamp, seat belt lamp, genertor warning lamp, door jamb switches, key buzzer, etc. All those things you describe are related to the bcm. You did well to check the plugs and sockets on the bcm as if water gets on them all sorts of gremlins result. This is a real problem with the convertible, but if you had a windshield leak that dripped down on the bcm it would be the same with your coupe body.
The bcm also is part of a two wire (twisted together) digital communication network that includes the pcm and the cluster so if the 2.5V +/-bias on that network failed it could impact the engine communication and starting/running. The bias, I believe is generated in the bcm. So continue to check for resistance to grounds from the fuse sockets to identify if anything other than 13 is involved. And you might want to recharge the battery in case that has been dragged down. Otherwise you could mistake a symptom due to weak battery to a short circuit.
I don't know what to make of the serial number issues.
Please let me know what you learn.
Roland

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QUESTION: IOD is the ignition off drawdown fuse, it supplies power to circuits that need power when the car is not in use. My vehicle does not use the #13 fuse. The manual that I picked up today Haynes 25030 for the lebaron coupe refers to a logic module is this the same as the BCM referred to in othe models? The picture looks the same as my unit.
Thanks

Answer
Hi Tom,
Correct. I sent an additional comment that should show up on your email today. It is fuse 26 that is the IOD and that is no doubt what your refer to as explained in my comment. Yes, if it looks identical the "logic" is no doubt the BCM.
Roland