B1009

Diagnostic Chart:

CIRCUIT DESCRIPTION
The DTC B1009 is an internal fault in the Vehicle Interface Unit (VIU).

CONDITIONS FOR RUNNING THE DTC
The VIU will run this internal test at the beginning of every wake-up cycle. Battery voltage is at least 9.5 volts and no more than 15.5 volts.

CONDITIONS FOR SETTING THE DTC
The VIU fails the EEPROM test.

ACTION TAKEN WHEN THE DTC SETS
The customer may complain of loss of OnStar(R) functionality since the VIU will use ROM as a default.

CONDITIONS FOR CLEARING THE MIL/DTC
The VIU successfully completes the EEPROM tests.

DIAGNOSTIC AIDS
If B1009 sets intermittently, test battery positive voltage and ground for poor connections.