Component Testing

Multifunction Intake Air Sensor

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air Sensor.
NOTE:

A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT Sensor 1 by varying the sensor temperature while monitoring the sensor resistance. Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor (Delco) table for Hitachi Sensors. The resistance values should be in range of the table values.
   • If not within the specified range 

     Replace the B75C Multifunction Intake Air Sensor.

   • If within the specified range 
3. All OK.

Multifunction Intake Air Sensor

1. Test the IAT Sensor 2 by varying the sensor temperature while monitoring the air temperature with a thermometer. Compare the readings with the scan tool IAT Sensor 2 parameter. The values should be within 5%.
   • If not within the specified range 

     Replace the B75C Multifunction Intake Air Sensor.

   • If within the specified range 
2. All OK.

Turbocharger Boost/Intake Air Temperature sensor

1. Ignition OFF, disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.
NOTE:

A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT Sensor 3 by varying the sensor temperature while monitoring the sensor resistance. Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor (Delco) table for Delco Sensors. The resistance values should be in range of the table values.
   • If not within the specified range 

     Replace the B111B Turbocharger Boost/Intake Air Temperature sensor.

   • If within the specified range 
3. All OK.