Exhaust Pressure Sensor 1 or 2, Checking

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.

For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.

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

- 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. Refer to Wiring Diagrams for Pin locations.











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 removal and installation 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 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.