Q: Driver side headlights are dim. When I flash brights, the engine dies.

asked by on November 09, 2016

So the driver side headlights are working but they are very dim. The passenger side are nice and bright. I replaced the alternator with a new 145amp. It came with a 105amp reman. Before I replaced the alternator if I turned the brights on or just flashed them the engine would die. Now after replacing the alternator I can turn the brights on and leave them but if I pull the lever back to just flash them real quick the engine dies. Any thoughts on where to look or what could be the culprit?

My car has 162000 miles.
My car has an automatic transmission.

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Hi and thanks for contacting YourMechanic. First check the battery cables for a clean and corrosion free contact. If the battery is good, then there is a problem with the wiring in the steering column. There is a short crossing the lights system and the dimmer switch to the ignition power wire. Check the wires on the dimmer switch to see if there is a loose connection and if there is a burned wire. If the wires are good, then check the light switch for any burned wires and see if the wires are loose. If there is no issues with those wires, then follow the wires to the lights and see if there is a loose ground wire on the frame or fender. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can assist you with the headlights issue causing the engine to shut off.

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