GM Service Manual Online
For 1990-2009 cars only

Voltage is supplied to the Fog LPS Relay coil through circuit 317 when the following conditions are present:

    • The headlamp switch is in the HEAD position.
    • The fog lamp switch is in the ON position.

The fog lamps relay coil is grounded through the high beam filaments through circuit 11. The fog lamps relay performs the following functions through circuit 34:

    • Energizes voltage to the fog lamps
    • Applies voltage to the fog lamps

Since the coil of the Fog LPS Relay is grounded through the high beam filaments, the relay de-energizes any time the high beams are ON because the voltage is applied to both side of the relay coil.