headlights fading

1999 CHEVROLET CAVALIER

J.SHIP

MEMBER
1 POST

Electrical problem
1999 Chevy Cavalier 4 cyl Two Wheel Drive 122222 miles

when driving at night my headlights fade from bright to dim and back and forth. Same thing when high beams are on. Any suggestions?

Feb 15, 2009 at 2:07 AM

SQM

✓Experienced Mechanic
6,383 POSTS

Hello,

If you are noticing the headlight gets brighter as the engine revs up then it could be due to a bad alternator.
So checking the alternator should be a good first step.

Here is a guide on how to test the alternator:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.

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