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Q: My headlights flicker when I drive.

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My headlights seem to flicker when driving. They get brighter or dimmer without me changing anything. What's going on?

There are several factors that can cause headlights to flicker while driving. The more common problems could be related to the headlight bulbs themselves, a weak battery, or even the alternator starting to fail.

If those items are fine, however, then I would have to dig a little deeper and inspect the wiring, relays, switches, and the light sockets. Loose connections, worn-out switches, or burnt relays and sockets can all cause intermittent breaks in power.

Have your lights checked out by a certified mechanic sooner rather than later to keep you from getting stuck driving in the dark without headlights, and to prevent unnecessary damage to your electrical system.

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