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Circuit/System Verification

WARNING: This page is about a different car, the 2006 Buick Lucerne. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify that the following DTCs are not set: U1814, B1428.
  2. 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 Current 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