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Exhaust Pressure Sensor 1 Or 2, Checking

Observe all safety precautions: SAFETY PRECAUTIONS 

View clean working conditions: CLEAN WORKING CONDITIONS 

Prior to repair work, perform a preliminary check to verify the condition. Refer to 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 and workshop equipment required 

Test requirements 

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 Ω (+/- 500 Ω)

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

-- 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 Ω (+/- 300 Ω)

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

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.

Exhaust Pressure Sensor -G450- electrical harness connector terminal Engine Control Module (ECM) -J623- electrical harness connector T94 terminals or test box socket
1 14
2 79
3 34
Exhaust Pressure Sensor -G451- electrical harness connector terminal Engine Control Module (ECM) -J623- electrical harness connector T94 terminals or test box socket
1 14
2 79
3 11

Specified value: 1.5 Ω 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 .
  2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .