P0473

P0473-EXHAUST PRESSURE SENSOR 1 HIGH

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

Theory of Operation

The Exhaust Gas Pressure Sensor is used to measure exhaust gas pressure in the exhaust manifold. The Powertrain Control Module (PCM) provides a 5 Volt supply to the Exhaust Gas Pressure Sensor on the sensor supply circuit. The PCM also provides a ground on the sensor return circuit. The Exhaust Gas Pressure Sensor provides a signal to the PCM on the Exhaust Gas Pressure Sensor Signal circuit.

- When Monitored:
Ignition on.

- Set Condition:
The circuit voltage to the PCM is above 4.75 volts.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC

NOTE: If any 5 Volt supply DTCs are present, repair those DTCs before proceeding.

1. Turn the ignition on.
2. With the scan tool, read DTCs.

Is the DTC active?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.

2. (K373) EXHAUST PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Exhaust Pressure Sensor harness connector.
3. Disconnect the PCM C2 harness connector.
4. Turn the ignition on.
5. Measure the voltage on the (K373) Exhaust Pressure Sensor Signal circuit at the Exhaust Pressure Sensor harness connector.

Is there any voltage present?

Yes

- Repair the (K373) Exhaust Pressure Sensor Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

3. (K900) SENSOR GROUND CIRCUIT OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Measure the resistance of the (K900) Sensor Ground circuit between the Exhaust Pressure Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 4

No

- Repair the (K900) Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

4. EXHAUST PRESSURE SENSOR
1. Reconnect the PCM C2 harness connector.
2. Turn the ignition on.
3. While monitoring the scan tool, connect a jumper across the (K373) Exhaust Pressure Sensor Signal circuit and the (K900) Sensor Ground circuit at the Exhaust Pressure Sensor harness connector.

Did the scan tool display DTC P0472 active?

Yes

- Replace the Exhaust Pressure Sensor. .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace the Powertrain Control Module. Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.