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Q: Do I have ECM/PCM problems?

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I have issues with my jeep wrangler dash instrument panel lights going crazy, not only that when I drive it for a few and shut it off, I'm not able to crank it again till after it cools down a few. My mechanic also said he has checked Grounds ETC. Also he checked the Alternator to see if it was doing what it is suppose to do,,, It was showing REVERSE POLARITY. Is this something that the ECM/PCM would control? Also does it disturb the idle control of the Jeep? When he pulled the connector from the Alternator everything went away but the charge light for the battery, but reconnecting it brought back all the lights flashing, and erratic idle speed.

My car has 119343 miles.
My car has an automatic transmission.

A: Hello. If all of these parts were checked a...

Hello. If all of these parts were checked and they are fine then the problem typically lies in the integrated power control module. This is a computer built into the fuse box under the hood. It controls all of these electrical systems and commonly fails. If you want to have this electrical problem diagnosed, consider having a technician from YourMechanic come to your home or office to diagnose the electrical problem and repair the issue.

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