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P0641Powertrain (P)generic

Sensor Reference Voltage "A" Circuit Open

The computer detected that the 5-volt reference voltage supply wire to various sensors has broken or come loose, cutting off power to sensor circuits. This is a wiring open circuit or power supply problem affecting multiple sensors simultaneously. Engine performance will suffer significantly because the computer can't read critical sensor data, resulting in rough running, poor fuel economy, or stalling.

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