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Q: One of my car's headlights does not work

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One headlight had the low beam working intermittently, sometimes i would turn the car on it would work. Sometimes i turn it on and it doesn't. I transferred the light bulb to the good headlight to make sure the bulb was good and worked, it did indeed work. The high beam continued to work for a while. Now the high beam and low beam don't work at all. Seems like the light bulb for the low beam is a xenon projector type. They are aftermarket headlights.
My car has an automatic transmission.

A: Hello. There are 2 devices in the front wir...

Hello. There are 2 devices in the front wiring of your vehicle called "Signal Acquisition Modules." One is for the left side of the front, the other is for the right. They act as an electrical "router" and power distribution module for electrical loads up front. These modules take signal pulses from light switches and other controllers, and turn on power to the requested device.

The SAM units have fuses in them, just as a traditional box would. I would check the fuses in each SAM for both low and high beams, then check the igniters for the xenon low beams. If this seems a bit intimidating, I recommend having a certified mechanic, such as one from YourMechanic, come to your location to inspect for any electrical problems and suggest the needed repairs.

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