Circuit/System Testing
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the DIC switch assembly.
- Ignition OFF, test for less than 1 ohm between the low reference terminal 2 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance.
- Ignition OFF, test for less than 1 ohm between the ground terminal 5 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, verify that all of the scan tool DIC Switch parameters are Inactive.
- If any are not Inactive, test the appropriate signal circuit terminal 1 or terminal 3 for a short to ground. If the circuit tests normal, replace the IPC.
- Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool DIC Switch parameters, except the DIC Fuel Info. parameter, are Active.
- If any are not Active, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
- Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal 3 and ground. Verify the scan tool DIC Fuel Info. parameter is Active.
- If not Active, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the IPC.
- If all the circuits test normal, test or replace the DIC switch assembly.