GM Service Manual Online
For 1990-2009 cars only

Object Number: 29555  Size: LF
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Engine Controls Components
APP Module, Wastegte, EGR, and EGR Vent
OBD II Symbol Description Notice

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 less than .25 volt on APP 2 sensor.
    • Condition met for 2 seconds

Action Taken When the DTC Sets

    • The input from APP 2 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 sensor 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 2 position in volts and should read about 4.5 volts with throttle closed and ignition ON or at idle. Voltage should decrease at a steady rate as throttle is moved toward WOT. Also, 90% pedal travel is acceptable for correct APP operation. Scan APP 2 sensor while depressing accelerator pedal with engine stopped and ignition ON. Display should vary from about 4.5 volts when throttle was closed to about 1.5 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.

  1. This Step determines if P0222 is the result of a hard failure or an intermittent condition.

  2. 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?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Ignition ON, engine OFF.
  2. With the throttle closed, observe the APP 2 voltage on the Scan Tool.

Is APP 2 voltage less than or equal to the specified value?

0.25 V

Go to Step 4

Go to Step 3

3

DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored, refer to those tables(s) first.

Are additional DTCs stored?

--

Go to the Applicable DTC Table

Go to Diagnostic Aids

4

  1. Disconnect the APP sensor electrical connector.
  2. Use the J 39200 in order to probe the APP 2, 5 volt reference circuit at APP harness.

Is APP 2 voltage greater than the specified value?

5 V

Go to Step 5

Go to Step 6

5

Use the J 39200 in order to probe APP 2 sensor signal circuit at the APP sensor harness.

Is APP 2 voltage greater than the specified value?

5 V

Go to Step 10

Go to Step 8

6

  1. Ignition OFF.
  2. Disconnect the PCM and check the 5 volt reference circuit for an open or short to ground.
  3. If the 5 volt reference circuit is open or shorted to ground, repair it as necessary.

Was the 5 volt reference circuit open or shorted to ground?

--

Go to Step 13

Go to Step 7

7

Check the 5 volt reference circuit for a poor connection at the PCM and replace the terminal if necessary.

Did the terminal require replacement?

--

Go to Step 13

Go to Step 12

8

  1. Ignition OFF.
  2. Disconnect the PCM, and check the APP 2 signal circuit for an open, or a short to ground.
  3. If the APP 2 sensor signal circuit is open or shorted to ground, repair it as necessary.

Was the APP 2 signal circuit open or shorted to ground?

--

Go to Step 13

Go to Step 9

9

Check the APP 2 sensor signal circuit for a poor connection at the PCM and replace terminal if necessary.

Did the terminal require replacement?

--

Go to Step 13

Go to Step 12

10

Check for a poor electrical connection at the APP sensor.

Was a repair performed?

--

Go to Step 13

Go to Step 11

11

Replace the APP module. Refer to Accelerator Pedal Position Module Replacement .

Is the action complete?

--

Go to Step 13

--

12

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?

--

Go to Step 13

--

13

  1. Use the Scan Tool in order to select DTC, Clear Info.
  2. Start engine and idle at normal operating temperature.
  3. Select DTC, Specific, then enter the DTC number which was set.
  4. Operate vehicle within the conditions for setting this DTC as specified in the supporting text.

Does the Scan Tool indicate that this diagnostic Ran and Passed?

--

Go to Step 14

Go to Step 2

14

Using the Scan Tool, select Capture Info, Review Info.

Are there any DTCs displayed that have not been diagnosed?

--

Go to the Applicable DTC Table

System OK