Circuit/System Testing - Single Generator (w/o K76) (Diesel)
WARNING: This page is about a different car, the 2009 GMC 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.
- Ignition OFF, disconnect the X1 harness connector at the generator.
- Ignition ON, test for less than 1 V between the signal circuit terminal 1 and ground.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
- Engine running, test for greater than 3.5 V between the signal circuit terminal 1 and ground.
- 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 ECM.
- If the circuit tests normal, test or replace the generator.