2000 - 2999: 2641

2641-EXHAUST PRESSURE SENSOR PLAUSIBILITY





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.

1. EXHAUST PRESSURE SENSOR CONTAMINATED/FOULED

NOTE: If any 5-Volt reference voltage DTCs are present, repair those DTCs before proceeding with this diagnostic procedure.

1. Remove the Exhaust Pressure Sensor.
2. Visually inspect the Exhaust Pressure Sensor for contamination or oil fouling.
Were there any signs of contamination on the sensor?

Yes

- Clean and reinstall the sensor.
- Perform the ECM VERIFICATION TEST. Verification Tests

No

- Go To 2

2. CHECKING THE EXHAUST PRESSURE SENSOR READING

NOTE: The engine temperature must be below 140°F(60°C) before performing this test.

1. Turn the ignition on.
2. If the engine was running allow for the Exhaust Pressure Sensor to settle.
3. With a scan tool compare the readings of the Exhaust Pressure Sensor with BARO Sensor.
4. The sensors should read approximately the same. The difference should be no greater than 1.015 psi (70hPa).
Are the pressure readings OK?

Yes

- Perform the INTERMITTENT DTC diagnostic procedure. Component Tests and General Diagnostics

No

- Go To 3

3. CHECKING THE EXHAUST PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT
1. Turn the ignition off.
2. Disconnect the Exhaust Pressure Sensor harness connector.
3. Turn the ignition on.
4. Using a Volt meter, measure the voltage of the Exhaust Pressure Sensor 5-Volt Supply circuit at the Exhaust Pressure Sensor harness connector.
Is the voltage reading between 4.9 and 5.2 Volts?

Yes

- Go To 4

No

- Repair the open or high resistance in the Exhaust Pressure Sensor 5-Volt Supply circuit.
- Perform the ECM VERIFICATION TEST. Verification Tests

4. CHECKING THE EXHAUST PRESSURE SENSOR SIGNAL CIRCUIT
1. Turn the ignition off.
2. Disconnect the ECM C1 harness connector.
3. Using an ohmmeter, measure the resistance of the Exhaust Pressure Sensor Signal circuit between the Exhaust Pressure Sensor harness connector and the ECM C1 harness connector.
Is the resistance less than 5.0 Ohms?

Yes

- Replace the Exhaust Pressure Sensor.
- Perform the ECM VERIFICATION TEST. Verification Tests

No

- Repair the open or high resistance in the Exhaust Pressure Sensor Signal circuit.
- Perform the ECM VERIFICATION TEST. Verification Tests