1986 capri RS * now with pics* huge pics sorry
Reply #35 –
Park on a hill and slam the trunk. That's how it got me.
The inertia switch's mechanism is a small steel ball sitting in a funnel, held in place by a magnet underneath it. With a good enough thump, the ball breaks free of the magnetism, rolls up the side of the funnel, and hits the lever above it, which triggers the other bits that make up the "switch" part. Besides actual impacts, the magnet may get weaker over time, letting the ball break free with any little bump.
The easiest way to rule it out as the problem is to remove it from the circuit.... unplug it, and use a jumper wire in its place.
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