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Q: I have a engine code P1684 what does it mean? Thanks

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I have a check engine light on my car P 1684 what does it mean and what should I do?

My car has 113800 miles.
My car has an automatic transmission.

A: The fault code P1684 means that power to yo...

The fault code P1684 means that power to your powertrain control module (PCM) was interrupted. The most common cause of this is because of a weak battery. When the car is stated, the voltage drops low enough that it cuts power to the PCM for just a brief moment, which will set the fault. It can also be caused by a wiring issue to the PCM, or a bad connection in the battery cable. It may or may not cause issues with drivability. The fault should be thoroughly diagnosed by a qualified technician, such as one from YourMechanic.

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