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Q: When I use the turn signals, both tail lights blink like hazard lights.

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Hello! I need help with a tail light problem. This morning I got pulled over and given a warning about one of my brake lights not turning on when I use the brake, so I got home and fixed it doing some rewiring. It worked. Until I noticed the right side didn't work. So I fixed that as well. Now both brake lights work. Now here's the problem, I turned on the blinker to the left signal and the tail lights both flash like if the hazard light was on. What do I do?

My car has 10000 miles.
My car has an automatic transmission.

A: Hello. Without knowing exactly what wiring ...

Hello. Without knowing exactly what wiring work was performed its nearly impossible to say definitively what the issue is. The brake light circuit and the turn signal circuit have crossed paths somewhere. The wires carrying the power supply from the turn signal switch is connected or touching the brake wires. The hazard light button is essentially an additional power source and switch for the turn signal circuit. With both brake lights blinking, the hazard light circuit may be crosses in as well.

Do you own a voltmeter or a way to measure available voltage? You are going to need to trace the wiring work you performed and find where the connection is jumping circuits. Having an official repair manual or wiring diagram will help a lot. Make sure once your issue is found that the wires are secured properly and protected from the elements and from other circuits.

If you're unable to solve the issue yourself, have a certified technician, like one from YourMechanic, come to your location to diagnose the issue with your turn signals and help you make the right repair.

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