GM Service Manual Online
For 1990-2009 cars only

Accessory

Scan Tool Parameter

Units Displayed

Typical Data Value

Operating Conditions: Ignition in RUN, Engine OFF, All Doors Closed, Park Brake Applied (DRLs OFF)

Rear Defog Relay Cmd.

On/Off

Off

Rear Defog Relay Fdbk.

High/Low

Low

Rear Defog Switch

On/Off

Off