I have a 1990 Chev p/u brake lights don't work . Fuses / Bulbs and Brake light switched replaced still nothing .Turn signals and running lights work also no 4 way flashers ?
Any thoughts ?
Did you use a test lite and check voltage at stop fuse? At the stop lamp switch, orange wire is voltage to stop switch for stop lamp. When switch is activated white wire carries voltage to turn signal switch for stop lamps. The lower brake lites are wired through the turn signal switch. At the rear, the stop and turn use the same bulb filament, just, not at the same time. Anything electrical check voltage and ground, first. Because turn works, I think ground is ok. My wiring diagrams on this model year aren't great.
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