P0228

Diagnostic Chart:

Wiring Diagram:

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.

Conditions for Setting the DTC

^ The PCM performs this DTC diagnostic continuously.

^ The signal voltage on the APP 3 sensor is greater than 4.75 volts.

^ All diagnostic conditions met for 2 seconds.

Action Taken When the DTC Sets

^ The input from APP 3 sensor is ignored.

^ This DTC will not turn on the Service Throttle Soon lamp by itself.

^ 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

There are no driveability issues associated with the APP module unless a DTC is present. The most likely causes of this DTC are poor connections or the sensor itself. The least likely is a PCM problem.

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 the Diagnostic Table.

2. This step determines if P0223 is a hard failure or an intermittent condition.

5. This step will check for an open in the ground circuit.