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Q: Is my problem my ECM relay?

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My truck sometimes allow me to get to my destination but once there and ready to leave it will not crank. I've had to wait up to 1 hour before or maybe even 5 mins and it cranks up. While headed to the dealership it completely turned off on the highway. I had to have it towed home and now the battery is dead from trying to crank it.
My car's transmission is unknown to me.

A: Hello and thank you for contacting YourMech...

Hello and thank you for contacting YourMechanic. First you will need to charge or replace your battery. Most of the time, if a battery has a burned cell or will not hold a charge, then it causes a lot of errors within the electronics of a vehicle.

Once you have a good battery, test drive the vehicle to see if any problems come back. If the problems come back, then check the wires to the battery and to the main fuse box to ensure that they are tight. Then check the power and ground wires to the ECM. If all of the wires are good, try wiggling the ignition switch to see if you can duplicate the problem without moving the vehicle. If the engine cuts out when moving the key around without turning off the engine, then the ignition switch needs replaced. If not, then the ECM needs replaced. If you need further assistance diagnosing the no start, then have a professional technician, like one from YourMechanic, help you with your vehicle.

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