Charge Air Pressure Sensor/Intake Air Temperature Sensor, Checking

Observe all safety precautions: SAFETY PRECAUTIONS

View clean working conditions: CLEAN WORKING CONDITIONS

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 

• Multimeter
• Wiring diagram

Test conditions 

• The Motronic Engine Control Module (ECM) - J623- fuses OK.
  Fig 1: Fuses On E-Box In Engine Compartment, Left Side

  Courtesy of AUDI OF AMERICA, LLC
• 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 (GND) connections between engine/transmission/chassis OK.
• Ignition switched off.

Test requirements 

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

Start diagnosis 

-- Remove the engine cover with air filter. Refer to appropriate service information.

Test sequence

-- Disconnect the Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72- electrical harness connector -1-.

On the right side, on the compressor with the charge air cooler. Note: The intake air temperature sensor 2 -G430- / charge air pressure sensor 2 -G447- are arranged as mirror images of each other.

-- Start engine and let it run at idle.

-- Using a multimeter, check the Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72- electrical harness connector terminals 1 to 2 for voltage.

Specified value: min. 4.5 V

-- Switch the ignition off.

If the specification was obtained:

-- Replace the Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72-.

If the specification was 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 Motronic Engine Control Module (ECM) -J623-. Refer to appropriate service information.

-- Using a multimeter, check the Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J623- electrical harness connector T94 terminals for an open circuit according to wiring diagram.

Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72- electrical harness connector terminals	Motronic Engine Control Module (ECM) -J623 - electrical connector T94 terminals or test box sockets
1	7
2	63
3	86
4	38

Specified value: 1.5 Ω max.

If the specification was not obtained:

-- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).

-- 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 if the voltage supply was OK:

-- Replace the Charge Air Pressure Sensor/Intake Air Temperature Sensor -G31/G72-.

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

-- Replace the Motronic Engine Control Module (ECM) -J623-. Refer to appropriate service information.

-- Install the engine cover with air filter.

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 .