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Q: I try to start the car by the jump box. I had the cables in the wrong way so now it's not working

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All the fuses the all good what you think it's ECM or there's something else

My car has 65000 miles.
My car has an automatic transmission.

Hi there. Jump starting the battery using reversed polarity can create all kinds of electrical issues for your vehicle. This may have internally shorted the battery, and a replacement battery is highly recommended. Circuit tests should be performed once the battery has been replaced.

If the engine turns over and doesn’t start. All the fuses under hood and in/under the dash need to be checked. Any number of components could have been affected by the reversed polarity, such as the ignition switch, relays, alternator, ECM (engine control module), BCM (body control module), etc. If you would like to have this all scoped out, a certified professional from YourMechanic can come to your car’s location to diagnose your vehicle’s battery issue and track down any other problems.

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