Component Testing
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
You must perform the Circuit/System Testing in order to verify the integrity of the exhaust differential pressure sensor circuits before proceeding with Component Testing.
NOTE:
You must perform the Repair Verification after completing the Component Testing.
- Ignition OFF, remove the exhaust pressure differential pressure sensor.
- Install a 3A fused jumper wire between the 5V reference circuit terminal 3 and the corresponding terminal of the differential sensor. Install a jumper wire between the low reference terminal 1 of the sensor and ground.
- Connect a DMM between terminal 2 of the differential sensor and ground.
- Ignition ON, with the J 23738-A:
Mityvac or J 35555:
Metal Mityvac connected to the pressure sensor rear pressure port, slowly apply vacuum to the sensor while monitoring the voltage. The voltage should vary and transition smoothly without any spikes or dropouts.
- If the voltage is erratic, replace the differential pressure sensor.
- If the differential pressure sensor tests normal, perform the Repair Verification.