Diagnostic Aids
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
- A short to ground in the run/crank ignition circuit of the run crank relay will cause an open fuse to the ignition switch. DTC B1428 should be current.
- A short to ground in the accessory wake-up serial data circuit will cause an open fuse to the ignition switch. DTC U1814 should be current.
- The power modes and controls are determined using BCM logic. Comparing the Body Control Module Power Mode data display parameters listed in Circuit/System Verification will determine if there is a power mode fault.