How can I diagnose the problem
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1994 Toyota Celica Question: The brake lights won't come on when I brake. I replaced the brake switch.
Answer #1ziptie12 November 11, 2012, 21:14Master
You can diagnose it by having a wiring diagram of the circuit , and an understanding of how it works , and by then using that information along with a volt-ohmmeter to test for power , ground and continuity as needed.Or check the wire harness in trunk along the hinge for a broken wire.
Replymaxgreco, November 13, 2012, 14:32Rookie
Replyziptie12, November 15, 2012, 21:51Master
was it a broken wire in the trunk harness?
Replymaxgreco, November 16, 2012, 16:13Rookie
Don't know yet did not have time to test. I will post results soon.