P0641
DTC P0641
Circuit Description
The powertrain control module (PCM) provides a 5-volt reference to the following sensors:
- The throttle position (TP) sensor 1
- The accelerator pedal position (APP) sensor 2
- The engine cooling fan speed sensor
- The A/C pressure sensor
- The fuel tank pressure (FTP) sensor
- The oil pressure sensor (OPS)
The PCM monitors voltage on the 5-volt reference circuit. If the voltage is higher or lower than required, DTC P0641 will set.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
- The PCM detects a voltage that is higher or lower than required on the 5-volt reference circuit.
- The above condition is present for 1 second.
Action Taken When the DTC Sets
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
Conditions for Clearing the MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.
Step 1 - 2:
Step 3 - 6:
Step 7 - 12:
