Intake Air Temperature Sensor -G42- / Manifold Absolute Pressure Sensor -G71-, Checking

Function

Air mass and charge pressure are two factors used for engine load management. For this purpose, the re are several sensors with absolutely identical functions. They measure the intake air temperature and the intake manifold pressure. The first sender unit is located upstream of the throttle valve control module J338 and contains the following senders:

• - Intake air temperature sensor G42
• - Manifold absolute pressure sensor G71

They measure the pressure and temperature of the air in each individual cylinder bank. The values measured here correspond to the actual air mass in the cylinder Bank(s).

Special Tools And Workshop Equipment Required 

• Multimeter
• Wiring Diagram
• Scan Tool

Test requirements

• Fuses OK.
• Battery voltage OK
• Switch OFF all electrical and electronic accessories.
• Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
• Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
• Coolant Temperature: ≥ 80 °C.
• Observe all safety precautions: SAFETY PRECAUTIONS
• View clean working conditions: CLEAN WORKING CONDITIONS

Test Procedure