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Q: When headlights are on, turn signals do not work - 1979 Ford F-100

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When my truck's headlights are on, the right turn signal does not work and the tail lights go from bright to dim. The truck can be running while it is just sitting parked and the same problems occur with the headlights, turn signals and tail lights. I have changed the bulbs but the problem still exists. What do you suggest that I do to fix this?

A: If the items share a common ground or power...

If the items share a common ground or power circuit, there could be a loose connection or a bit of corrosion in the shared circuits in the steering column. The cross contact from corrosion growing across circuits can cause similar symptoms. If you would like, a certified technician from YourMechanic can come to your home or office and inspect your electrical wiring.

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