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Q: With the ignition off the truck tries to start its self when you go to hook up a battery

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The starter seems to be good and batteries fully charged but when you go to hook up the battery it automatically tries to turn the starter over all wires are correctly mounted and the ignition is off with no keys in it

My car has 182500 miles.
My car has an automatic transmission.

Hi there. What you are describing is typically an indication of a damaged ignition relay. Essentially, what’s happening is when you attach the battery terminals, power is bypassing the ignition relay and being sent directly to the starter relay. This is caused typically by a faulty ground wire connection or damage to other electrical components within the ignition relay. This can be a very complex issue to correctly diagnose, which is why you should have a professional mobile mechanic complete an electrical problem inspection.

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