Circuit/System Verification
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- 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 Body Control Module, 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 (circuits) 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 | Currant Power Mode | Ign. Off/Run/Crank (Off/Run Crank voltage circuit) |
Ignition Accessory/Run (Accessory voltage circuit) |
Ignition Run/Crank (Ignition 1 Voltage circuit) |
|---|---|---|---|---|
| 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 |
- If any parameters are incorrect in any key position, proceed to the Circuit/System Testing or Component Testing below.