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Crazy electrical problem with Town and Country

Used 2000 Town & Country is a great ride EXCEPT it occasionally will not start. All the electrical systems work except the starter does not activate. No connection to temp. Happens when cold or when hot. Sometimes cuts off when running and will not start. With the ignition in run position prior to starting, the check engine light does not light up and starter doesn’t work. When in run and the check engine light comes on the starter will work and starts easily. Sometimes in run position the check engine light is flashing and starter will activate for split second before light and starter quit. It’s gone for months without happening and I fantasize that it has miraculously healed itself then it will happen once, or perhaps daily for a week. Sometimes wait +/- 1/2 hour and it cranks right up. Sometimes it won’t crank for a day. Have replaced computer twice, various sensors (cam shaft sensor?..I’m not a mechanic) Our very competent mechanic won’t let us bring it near his shop. It has driven him and us crazy. He didn’t charge us for numerous hours spent puzzling over it if we just promise not to bring it back in. Next thing to try is the infusion of 12 gauge buckshot into all the vital components (the car or me. I’m not sure which!)

Which computer did you change? The PCM? How about the BCM? The security module? There are several computer modules in this van. The BCM will not allow the engine to start if it doesn’t get approval from the security module. The problem could be in either one.

Can you use a jumper wire to run the starter when the ignition fails to work? Does it start up then?

From what you state about the clues to the trouble it sounds to me that the intermittent trouble could be either with the ignition switch, the power line to it or after it, or in the power lead to the ECU for the CEL light. I’m not sure if the BCM controls the CEL light but knowing the CEL light doesn’t work when the trouble happens is a very good clue to the problem. If the BCM does control the CEL light then I would check to see if there is a relay in the power circuit to the BCM, or to whatever controls the CEL light. If there is a relay involved it may have intermittent contacts and replacing it may fix the problem. There may also just be a faulty pin connection in a connector and simply reconnecting any connectors that carry power to the module will fix the trouble. It would be nice to know if the gauges and other dash warning lights work ok when the trouble occurs. Any clues like this can help pin down the trouble. Because the trouble appears to be due to a lack of power getting to certain things knowing what isn’t working can help pin down the the trouble area while refering to the factory wiring diagrams. You need to find a good shop that understands how to locate intermittent electrical problems.