P0651
DTC P0651
CIRCUIT DESCRIPTION
The engine control module (ECM) uses the 5-volt reference 2 circuit as a sensor feed to the following sensors:
- The manifold absolute pressure (MAP) sensor
- The accelerator pedal position (APP) 1 sensor
- The throttle position (TP) 2 sensor
If the ECM detects the voltage on the 5-volt reference 2 circuit is outside a valid range, DTC P0651 sets.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0651 5-Volt Reference 2 Circuit
CONDITIONS FOR RUNNING THE DTC
- The ignition is ON.
- DTCs P0601, P0602, P0604, P0606, P1621 are not set.
- DTC P651 runs continuously when the above conditions are met.
CONDITIONS FOR SETTING THE DTC
- The ECM detects the voltage on the 5-volt reference 1 circuit is less than 4.88 volts or greater than 5.13 volts.
- The above condition is present for longer than 0.5 second.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the 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
