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Q: Battery connected backwards and won't start

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The battery in my car was connected backwards. I replaced the blown relays that are in the fuse box. There is full power to all acc, but the car just won’t crank and it won’t turn over. So I jump-started the starter and it’s working, but it’s not getting the signal. Everything else in the car works fine, as far as I can tell. What should I do next to find the solution?

Hello. Most of the time this is caused by a failed main fuse. If the fuses have been replaced then it is more than likely a bad module. In most cases the engine control module will fail when the battery is jumped backwards.

The computer needs to be scanned with a scan tool to see if it is powering up and seeing sensor signals. If you need to have this done, consider YourMechanic, as a certified mechanic can come to your home to diagnose your starting problem. An accurate repair can be made one the problem has been pinpointed.

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