Circuit/System Testing
WARNING: This page is about a different car, the 2008 Isuzu i-370, 2008 Isuzu i-290, 2008 GMC Canyon, and 2008 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the inside rearview mirror.
- Ignition ON, test for 9.5-10.5 volts between the signal circuit terminal 10 and ground.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the CIM.
- If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the CIM.
- Test for test for 9.5-10.5 volts between the signal circuit terminal 10 and the drain circuit terminal 2.
- If less than the specified range, test the drain circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the CIM.
- If all circuit test normal, replace the cellular microphone.