Expert: Robert Summers - 11/13/2007

Question
Hello, I have a chevy monte carlo, 1996 LS.

Recently, I have noticed that, while driving at night, my head  and interior lights have started to go dim, then back to normal light every time my car reaches above 55 mph. It does not do this on idle, nor on any other speed below 55. the lights do not go completely out, they just dim, then return to normal. I dont notice it happening with any road dips or bumps. only when the the driving speed reaches 55 +

I am worried that i will lose these lights completely, What can i do to help get this fixed? My husband is good with fixing cars, and small planes, but is stumped. any help would be appreciated :)



thank you for your time in advance.

Lori.

Answer
Hi Lori...does this car have daytime running lights...if it does check the running light module...if not check for intermittent bad ground in the light circut.i would also check the alt output. it should be at 14 volts ot better.could be bad regulator in the alt.  hope this helps