P2127
DTC P2127
CIRCUIT DESCRIPTION
The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted in the pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the position of the accelerator pedal. The powertrain control module (PCM) supplies a separate 5-volt reference and low reference circuit for each of the APP sensors.
The APP sensor 1 signal voltage increases as the pedal is depressed, from approximately 1 volt at rest to above 4 volts when fully depressed. The APP sensor 2 signal voltage increases as the pedal is depressed, from approximately 0.5 volts at rest to more than 2 volts with the accelerator pedal fully depressed.
If the PCM detects that the APP sensor 2 signal voltage is too low, this DTC sets.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P2127 Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage
CONDITIONS FOR RUNNING THE DTC
- The ignition is ON.
- DTC P2127 runs continuously.
CONDITIONS FOR SETTING THE DTC
The APP sensor 2 voltage is less than 0.2 volts for less than 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 DESCRIPTION
Steps 1-11:
Steps 12-14:
The numbers below refer to the step numbers on the diagnostic table.
5. This step tests the signal and 5-volt reference circuits.
12. After replacing the PCM, a new minimum throttle position and idle speed must be established.