Circuit Description
The Accelerator Pedal Position (APP) module provides a voltage signal that changes relative to accelerator pedal position. There are three sensors located within the APP module that are scaled differently. This is a type D DTC.
Conditions for Setting the DTC
| • | Voltage is greater than 4.75 volts for 2 seconds on APP 3 sensor. |
| • | Conditions met for 2 seconds. |
Action Taken When the DTC Sets
| • | The input from APP 3 sensor is ignored. |
| • | A current and history DTC will set but it will not turn ON the Service Throttle Soon lamp. |
| • | The throttle will operate normally as long as there is only one malfunction present. If two different APP sensors have a malfunction, the Service Throttle Soon lamp will light and the PCM will limit power. If three APP sensors have a malfunction present, the Service Throttle Soon lamp will light and the PCM will only allow the engine to operate at idle. |
Conditions for Clearing the MIL/DTC
| • | A History DTC will clear when forty consecutive warm-up cycles that the diagnostic does not fail (coolant temperature has risen 5°C (40°F) from start up coolant temperature and engine coolant temperature exceeds 71°C (160°F) that same ignition cycle. |
| • | Use of a Scan tool |
Diagnostic Aids
A scan tool reads APP 3 position in volts. Should read about 4.0 volts with throttle closed and ignition ON or at idle. Voltage should decrease at a steady rate as throttle is moved toward Wide Open Throttle (WOT). Also, 90% pedal travel is acceptable for correct APP operation. Scan APP 3 sensor while depressing accelerator pedal with engine stopped and ignition ON. Display should vary from about 4.0 volts when throttle was closed to about 2.0 volts when throttle is held at Wide Open Throttle (WOT) position.
Test Description
Number(s) below refer to the Step number(s) on Diagnostic Table.
-
This Step will determine if DTC P0228 is the result of a hard failure or an intermittent condition.
-
This Step checks the PCM and wiring.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Important: Before clearing DTCs use the scan tool Capture Info to record freeze frame and failure records for reference, as data will be lost when Clear Info function is used. Was the On-Board Diagnostic (OBD) System Check performed? | -- | ||
Is APP 3 greater than or equal to the specified value? | 4.75 V | |||
DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored, refer to the applicable DTC table(s) first. Are additional DTCs stored ? | -- | Go to the Applicable DTC Table | Go to Diagnostic Aids | |
4 |
Is the test light ON? | -- | ||
5 | Use a fused jumper wire in order to jump the APP 3 signal circuit to the APP 3 ground circuit at the APP harness connector. Does the scan tool display the APP 3 voltage less than the specified value? | 0.25 V | ||
6 |
Was the APP 3 sensor signal circuit open? | -- | ||
7 |
Was APP 3 sensor ground circuit open? | -- | ||
8 | Check for a poor elecrtical connection at the APP sensor. Was a repair performed? | -- | ||
9 | Replace the APP module. Refer to Accelerator Pedal Position Module Replacement . Is the action complete? | -- | -- | |
10 | Replace the faulty PCM. Important: If the PCM is faulty, the new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Is the action complete? | -- | -- | |
11 |
Does the Scan Tool indicate that this diagnostic Ran and Passed? | -- | ||
12 | Using the Scan Tool, select Capture Info, Review Info. Are any DTCs displayed that have not been diagnosed? | -- | Go to the Applicable DTC Table | System OK |
