Advanced Diagnostics

DTC P0641: Sensor Reference Voltage A Circuit Malfunction




General Description
The powertrain control module (PCM) is equipped with a power supply to supply 5 V to each sensor, and it supplies stable power to each sensor as a sensor reference voltage.

The voltage value to the sensor is loaded in the CPU of the PCM (A/D input), and when the sensor voltage is above or below the specified voltage range for a set time, a malfunction is detected and a DTC is stored.




Monitor Execution, Sequence, Duration, DTC Type, OBD Status




Enable Conditions

Malfunction Threshold
The sensor reference voltage is 5.4 V or more, or 4.6 V or less, for at least 2 seconds.

Diagnosis Details

Conditions for illuminating the MIL
When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the PCM memory.

Conditions for clearing the MIL
The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the diagnostic runs.

The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.