Exhaust Pressure Sensor: Testing and Inspection

Exhaust Pressure Sensor 1 or 2, Checking

Observe all safety precautions: => [ Safety Precautions ] Safety Precautions

View clean working conditions: => [ Clean Working Conditions ] Clean Working Conditions

Prior to repair work, perform a preliminary check to verify the condition. Refer to => [ Preliminary Check ] Preliminary Check.

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

Special tools, testers and auxiliary items required

• Multimeter

• Wiring diagram

Test requirements

• The engine control module fuses OK

• The battery voltage at least 12.5 V

• All electrical consumers switched off

• Engine MUST be at room temperature.

• The ignition switched off

Test procedure

Make sure the engine is at room temperature.

- Disconnect the Exhaust Pressure Sensor (G450/G451) electrical harness connector.

Checking internal resistance

- Using a multimeter, measure the resistance between the terminals 1 and 2 of the Exhaust Pressure Sensor (G450/G451).

Specified value for G450 (sensor 1): 6880 ohms (+/- 500 ohms)

Specified value for G451 (sensor 2): 69.7K ohms (+/- 1000 ohms)

- Using a multimeter, measure the resistance between the terminals 2 and 3 of the Exhaust Pressure Sensor (G450/G451).

Specified value for G450 (sensor 1): 4028 ohms (+/- 300 ohms)

Specified value for G451 (sensor 2): 9720 ohms (+/- 300 ohms)

If any specified value was not obtained:

- Replace the Exhaust Pressure Sensor (G450/G451). Refer to the repair information.

If the specified value was obtained:

Checking the power supply

Switch the ignition ON.

- Using a multimeter, measure the voltage of the Exhaust Pressure Sensor (G450/G451) harness connector terminal 1 to ground.

Specified value: near 5.01 V.

- Using a multimeter, measure the voltage of the Exhaust Pressure Sensor (G450/G451) harness connector terminal 3 to ground.

Specified value: near 5.77 V.

- Using a multimeter, measure the voltage of the Exhaust Pressure Sensor (G450/G451) harness connector terminal 2 to Battery Positive.

Specified value: Battery voltage.

- Switch the ignition OFF.

If any of the specified values were Not obtained:

Checking wiring

If the manufacturers test box is being used, perform the following step.

- Install the test box.

If the manufacturers test box is not being used, perform the following step.

- Remove the Engine Control Module (ECM) (J623). Refer to the repair information.

- Using a multimeter, check the Exhaust Pressure Sensor (G450) electrical harness connector to the Engine Control Module (ECM) (J623) electrical harness T60 connector for resistance.











Specified value: 1.5 ohms Max.

If the specified value was Not obtained:

- Check the wiring for a short circuit to each other, Battery positive, Ground or high resistance.

- If necessary, repair the faulty wiring connection.

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If no malfunction is detected in the wiring and the voltage readings were Not correct:

- Replace the Engine Control Module (ECM) (J623). Refer to the service information for procedures.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 0A.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 0A.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Readiness Code.