Only check the lights that are supposed to be on when the warning light comes on. Brake lights, blinkers, rear-fog, will only trip the warning system once they're turned on.

If the parking/running lights turn on the warning, it is either one of the front two corners, one of the tail and side-markers in the rear, or the license-plate lights (or their connections & grounds). Don't complicate with lights that aren't on, eliminate ones that aren't.

If the warning comes on with the brake pedal, it's the brake lights, with the headlamps, the headlamps, with the blinker, a blinker, ... or the wiring/grounds.

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Gone to the dark side

- Jeff