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Q: My Jeep has a full battery but is not starting every time I go to start the car.

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The car will sound like it is about to start but simply does not crank. I have a 100% battery but is simply will not crank. I feel like there is something electrical wrong. If I wait for the "Lightning Bolt" Light on my dash that I believe is for the Electronic Throttle Control to go off after about 15-20 seconds, the car will often start once the light is off? What the heck is going on.

My car has 80000 miles.
My car has an automatic transmission.

A: Hi there. There are several possible causes...

Hi there. There are several possible causes for the lightening bolt to remain on. The PCM (powertrain control module) has recognized an electrical fault in the ETC (electronic throttle control) system and disables the starter relay, creating a no crank situation. This could be from a faulty APP (accelerator pedal position) sensor, a faulty TPS (throttle position sensor) at the throttle body, or an electrical fault in the TIPM (totally integrated power module). Replacing components without proper diagnoses could be expensive and time consuming without a proper resolution. I recommend having your vehicle’s cranking problem diagnosed and repaired by a certified technician, such as one from YourMechanic.

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