Charge Air Pressure Sensor/Intake Air Temperature Sensor, Checking

Special tools and workshop equipment required 

• Multimeter.
• Wiring diagram.

Test requirements 

• The Engine Control Module (ECM) - J623- fuses OK.
• Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• On vehicles with automatic transmission, selector lever in position "P" or "N".
• A/C switched off.
• Ground connections between engine/transmission/chassis OK.
• Ignition switched Off.

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start diagnosis 

-- Remove the engine cover.

Test sequence 

-- Disconnect the Charge Air Pressure Sensor -G31- electrical harness connector.

-- Start the engine.

-- Using a multimeter, check the Charge Air Pressure Sensor -G31- electrical harness connector terminals 1 to 3 for voltage.

Specified value: 4.5 to 5.2 V

-- Switch the ignition Off.

If the specified value was Not obtained: 

Checking wiring 

-- Remove the Engine Control Module (ECM) -J623-.

-- Using a multimeter, check the Charge Air Pressure Sensor -G31- electrical harness connector terminals to the Engine Control Module (ECM) -J623- electrical harness connector T91 terminals for an open circuit according to wiring diagram.

Charge Air Pressure Sensor -G31- electrical harness connector terminals:	Engine Control Module (ECM) -J623- electrical connector T91 terminals:
1	35
2	Empty cavity
3	32
4	55

Specified value: 1.5 Ω max.

If the specified value was Not obtained: 

-- Check the wiring for an open, high resistance or short to ground.

-- 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 supply was OK: 

-- Replace the Charge Air Pressure Sensor -G31.

If no malfunction is detected in the wiring and the voltage supply was Not OK: 

-- Replace the Engine Control Module (ECM) -J623-.

-- Install the engine cover.

Final procedures 

After the 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 .