Having problems with a 1992 FLTHCU. The signal lights are intermittent and brake light is not lighting up. Any suggestions? I have changed all the bulbs.
Get out your test light. You will need to chase some wiring. The signals & brake lights would be 2 separate issues on your make & model. For brake light. Remove your taillight lens. Use your test light to verify that only one contact has voltage (running light) with ignition switch turned on. If both contacts have voltage; one if your brake switches is stuck on. This might make it seem as if you have no brake light because the light does not get brighter when applying brake pressure. Inspect your taillight harness and taillight assembly. Make sure the harness is intact. Otherwise, start testing at your brake switches, front & rear. Test to verify voltage. Test your way from the switch and out. Pin point where, switched, voltage is lost. For the signal issue; you may have a week connection or ground if they work intermittently. Start testing at the signal housings and work your way toward your turn signal module. Your service manual has a map of your wiring harness. It can be a good reference.
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We even have an article on it In The Shop – Read It Here
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