Just joined and I'm having a problem with fog light wiring. Have looked in manuals, talked to other bonneville owners, even went to pontiac to no avail. does anyone have a fog light wiring diagram for a 94 bonneville? Thanks Harry

What trim level?
Daytime running lights?
Twilight Sentinel?

Its fairly simple:

"HOT" arrives at the top of the fog-lamp switch when either the headlight switch is pulled, or the lamp-control-module for twilight sentinal deems it to be dark enough.

The fog lamp switch lights the ON indicator at the switch itself, and also sends HOT down to the relay in position G of the "relay center" (right-hand-side under instrument panel).

The fog-lamp switch itself only triggers the relay. The diagram also shows that the relay can only be trigged in low-beam. Switching to high beam causes the lamp-control-module to remove the ground from this relay and make it inoperative.

To actually light the fog lamps "hot at all times" comes from fuse 6D 15 amps (in the instrument-panel fuse block under the left side). This goes to terminal 30 of the relay at position G, mentioned above.

When the relay is triggered as described above, terminal 30 is shorted internally to terminal 87, and the power goes directly to the fog lamps from terminal 87.

Oh, and if you DO NOT have the twilight sentinel, the high-beam disabling of the fog lamps is accomplished by another relay in postion C of the relay centre. terminal 30 and 87A of this relay are normally shorted to provide ground for activating the position G relay. When high-beams are on, the short in the position C relay is removed.

He'* talking about foglights, which are a seperate system.

At the lamps, the purple wire is hot, the black is ground. The relay is in the maxifuse relay center, but will only energize if your headlamp switch is in parking or headlight mode.

The fog-light relay wil energize when:

1. the headlight switch is pulled to PARK or HEADLIGHT..... AND....
2. the fog-light switch is ON,..... AND
3. the headlights are in LOW BEAM.

OR, if he has twilght sentinel, then it will energize when:

1. it is dark enough for the lamp-control-module, so it sends HOT to the fog-light-switch .... AND
2. the fog-light switch is ON,.... AND
3. the headlights are in LOW BEAM.


I am not sure what you mean by "separate system".... The fog lights and head lights are "tied together" in that:

1. the headlights must be activated by the switch (or by the lamp control module) before the fog lights will come on, AND
2. the headlamps, being ON, must ALSO be in LOW BEAM.


???

The fog lights are shown with the headlight wiring diagrams that I have access to. When he answers my questions I can send him the correct diagram.

PS - hboyd73 - PM me with an email address & I'll send you the pdf file.