Circuit Description
The accelerator pedal position (APP) module provides a voltage signal that changes relative to the accelerator pedal position. There are 3 sensors located within the APP module that are scaled differently.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The voltage is less than 0.25 volts on the APP 3 sensor. |
| • | The conditions were met for 2 seconds. |
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
| • | The driver information center, if equipped, may display a message. |
Conditions for Clearing the DTC
| • | 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 non-emission related diagnostic. |
| • | Clear the DTC with a scan tool. |
Diagnostic Aids
There are no driveability issues associated with the APP module unless a DTC is present. The most likely cause of this DTC are poor connections or the sensor itself. The least likely is a PCM condition.
A scan tool reads the APP 3 position in volts. The scan tool should read approximately 4 volts with the throttle closed and the ignition ON or during idle. The voltage should steadily decrease as the throttle is moved toward a wide open throttle (WOT). Also, 90 percent pedal travel is acceptable for correct APP operation. Scan the APP 3 sensor while depressing the accelerator pedal with the engine stopped and the ignition ON. The display should vary from approximately 4 volts when the throttle is closed to approximately 2 volts when the throttle is held at a WOT position.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step will determine if DTC P0227 is the result of a hard failure or an intermittent condition.
-
This step checks the PCM and the wiring.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |
Does the APP 3 voltage measure less than or equal to the specified value? | 0.25 V | Go to Step 4 | Go to Step 3 | |
The DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If any additional DTCs are stored, refer to those tables first. Are there any additional DTCs stored? | -- | Go to Diagnostic Aids | ||
4 |
Does the voltage measure at the specified value? | 5 V | Go to Step 5 | Go to Step 6 |
5 | Use the DMM in order to probe the APP 3 signal circuit at the APP harness. Does the APP 3 signal voltage measure greater than the specified value? | 4.8 V | Go to Step 9 | Go to Step 8 |
6 |
Did you perform a repair? | -- | Go to Step 12 | Go to Step 7 |
7 | Check the 5-volt reference circuit for a faulty connection at the PCM and replace the terminal if necessary. Refer to Wiring Repairs in Wiring Systems. Did you perform a repair? | -- | Go to Step 12 | Go to Step 11 |
8 |
Did you perform a repair? | -- | Go to Step 12 | Go to Step 11 |
9 | Check for a faulty electrical connection at the APP sensor. Repair the connection as necessary. Refer to Wiring Repairs in Wiring Systems. Did you perform a repair? | -- | Go to Step 12 | Go to Step 10 |
10 | Replace the APP module. Refer to Accelerator Pedal Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- |
11 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- |
12 |
Does the scan tool indicate the diagnostic passed? | -- | Go to Step 13 | Go to Step 2 |
13 | Does the scan tool display any additional undiagnosed DTCs? | -- | System OK | |
