GM Service Manual Online
For 1990-2009 cars only

Chevrolet

Battery voltage is applied at all times to the horn relay through circuit 1140 at the following terminals:

    • Terminal E6
    • Terminal E8

Ground is applied to the horn relay coil at terminal F8 through circuit 28 when one of the following actions occur:

    • A horn switch is pressed
    • The body control module (BCM) initiates a tamper/alarm cycle

The horn relay contacts close. Battery voltage is applied to the horns through circuit 29. Ground is applied to the horns through circuit 250 and G105. The horns continue to sound until one of the following actions occur:

    • The horn switch is released.
    • The tamper/alarm cycle ends.

Pontiac

Battery voltage is applied at all times to the horn relay through circuit 1140 at the following terminals:

    • Terminal E6
    • Terminal E8

A ground path is provided to the horn relay coil at terminal F8 through circuit 28 under the following conditions:

    • When the inflator module is pressed against a spring loaded ground plate in the steering wheel.
    • When the BCM initiates a tamper/alarm cycle

The horn relay contacts close with ground applied. Battery voltage is applied to the horns through circuit 29. Ground is applied to the horns through circuit 250 and g105. The horns continue to sound until one of the following actions occur:

    • The inflator module is released.
    • The tamper/alarm cycle ends.