turn signals and 4 way flashers are on different systems and use different flashers You would want to look for the turn signal relay, try putting on your 4-way hazard flashers so you can here the clicking noise of the relay, they might be under your dash. In my car it was underneath the dash directly in line with the steering column, above the brake pedal.
replace the combination switch on the turn signal stalk
Bulbs or turn signal flasher, maybe even the switch.
The flasher relay is in the hazard switch. The hazards work on my wife's S4 but the directionals don't. I found another posting that says that the relay is in the hazard switch. The fuse is fine.
A 1992 LeSabre wouldn't have a valet switch
Buick does not use a reset switch.
The trunk
This varies with model year.
On the transmission
GM vehicles do not have an inertia switch.
No it does not.
GM vehicles do not have an inertia switch.
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