Circuit/System Verification
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.
- Verify that the following DTCs are not set: U1814, B1428.
- If either of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- With a scan tool, access BCM, Power Mode data display list and compare all parameters listed with the corresponding ignition key position. The PMM Power Mode Parameters table below illustrates the correct state of these input parameters in correspondence to the ignition switch position. The circuits which the individual parameters are related to are in parentheses.
PMM Power Mode Parameters
| Ignition Switch Position | Current Power Mode | Ign. Off/Run/Crank (Terminal 5) |
Ignition Accessory/Run (Terminal 3) |
Ignition Run/Crank (Terminal 2) |
|---|---|---|---|---|
| Off Key Out | Off | Key Out/ACC | Inactive | Inactive |
| Off Key IN | Off | Key In/Off | Inactive | Inactive |
| Accessory | Accessory | Key Out/ACC | Active | Inactive |
| Run | Run | Run | Active | Active |
| Start | Crank Request | Crank | Inactive | Active |