P0641
DTC P0641
CIRCUIT DESCRIPTION
The powertrain control module (PCM) uses the 5-volt reference circuit as a sensor feed to the following sensors:
- The A/C pressure sensor
- The throttle position (TP) sensor 1
- The accelerator pedal position (APP) sensor 2
- The fuel tank pressure (FTP) sensor
- The supercharge inlet pressure (SCIP) sensor
- The barometric pressure (BARO) sensor
- The camshaft position (CMP) sensor
The PCM monitors the voltage on the 5-volt reference circuit. If the voltage is out of tolerance, the PCM will set DTC P0641.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0641 5-Volt Reference 1 Circuit
CONDITIONS FOR RUNNING THE DTC
- DTCs P0601, P0602, P0604, P0606, P1621, and P2610 are not set.
- The ignition is in unlock, accessory, run, or crank mode.
- The ignition voltage is greater than 5.2 volts.
- DTC P0641 runs continuously when the above conditions are met.
CONDITIONS FOR SETTING THE DTC
- The PCM detects a voltage out of tolerance condition 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.
TEST
