Exhaust Pressure Sensor: Testing and Inspection
Exhaust Pressure Sensor 1 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.
- Check the flexible hose and connections between the particulate filter and the pressure sensor for leaks or damage.
- Disconnect the Exhaust Pressure Sensor (G450) electrical harness connector.
Checking internal resistance
- Using a multimeter, measure the resistance between the terminals 1 and 2 of the Exhaust Pressure Sensor (G450).
Specified value: 2041 ohms (+/- 150 ohms)
- Using a multimeter, measure the resistance between the terminals 2 and 3 of the Exhaust Pressure Sensor (G450).
Specified value: 1201 ohms (+/- 150 ohms)
If any specified value was not obtained:
- Replace the Exhaust Pressure Sensor (G450). Refer to the Repair Manual.
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) harness connector terminal 1 to ground.
Specified value: near 5.01 V.
- Using a multimeter, measure the voltage of the Exhaust Pressure Sensor (G450) harness connector terminal 3 to ground.
Specified value: near 5.70 V.
- Using a multimeter, measure the voltage of the Exhaust Pressure Sensor (G450) 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 Manual.
- Using a multimeter, check the Exhaust Pressure Sensor (G450) electrical harness connector to the Engine Control Module (ECM) (J623) electrical harness T94 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).
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 ] Scan Tool Testing and Procedures.
2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Scan Tool Testing and Procedures.
3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.