GM Service Manual Online
For 1990-2009 cars only

Voltage is supplied to the backup lamps under the following conditions:

    • The ignition switch is in the RUN or START position
    • The backup lamp switch (manual transmission) or the park/neutral position switch is closed

The circuit contains two fuses, the B/U LP fuse and the VEH B/U fuse. Both fuses are located in the underhood fuse block. The B/U LP fuse protects the circuit between the B/U LP fuse and the VEH B/U fuse. The VEH B/U fuse protects the circuit between the underhood fuse block and the backup lamps.

Backup Lamps

Voltage is supplied from the B/U LP fuse to the backup lamp switch (manual transmission) or the park/neutral position switch (automatic transmission) when the ignition switch is in the RUN or START position. Whenever the gear selector is placed in reverse, the following actions occur:

    • The backup lamp switch (manual transmission) or park/neutral position switch (automatic transmission) closes.
    • Voltage is supplied to the backup lamps.

The backup lamps remain on as long as the switch is closed.