The switch that set this DTC, and its circuits, are built into the LH Front Power Window Switch assembly. When the left rear window switch is operated from the LH front power window switch assembly , the assembly, which contains an internal microprocessor, processes the switch input and then reports the switch activity in the form of an SBI message to the driver door module. If conditions are correct for window operation to occur, the driver door module sends a SBI message to the left rear door module to operate the window. The actual diagnostic software program for DTC B3477 is contained in the driver door module and the diagnostic is run no less than once every 300 milliseconds. Problems involving the door modules or the SBI may set other DTCs and affect the operation of the power door locks and the outside rear view mirrors.

If the driver door module detects that the SBI messages from the LH front power window switch assembly show that the left rear window switch has been in the Express Down position for 15 continuous seconds, this DTC will be set current. This diagnostic will not run if either DTC B1982 (Battery Voltage High) or B1983 (Battery Voltage Low) are current.

This DTC is dynamic, and as such, is current only while the problem is present. While this DTC is current, the driver door module will ignore the actuation of the left rear window switch.

The numbers below refer to the step numbers on the diagnostic table:

1. Perform the Power Door Diagnostic System Check prior to continuing the diagnosis of this DTC.

2. This repair procedure requires power window switch replacement.

3. Clear all DTCs following repair procedure completion.