My voltmeter goes from 14 to 10 when applying brakes. What causes this?
CONFEDSURG
MEMBER
1995 CHEVROLET SILVERADO
83,700 MILES
When applying brakes, the voltmeter goes from 14 to 10 gradually. There is no indication of stalling or other problem.
Sunday, February 12th, 2012 AT 5:34 PM
5 Replies
RASMATAZ
MECHANIC
75,992 POSTS
Check belt tension if okay-Have the alternator load tested-start here
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Sunday, February 12th, 2012 AT 5:47 PM
SATURNTECH9
MECHANIC
30,869 POSTS
So does it only do it while stepping on the brake no other time?Do you have a multimeter to do some testing?
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Sunday, February 12th, 2012 AT 5:48 PM
CONFEDSURG
MEMBER
2 POSTS
Yes, it only happens when stepping on the brake, no other time. I do not have a multimeter.
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Sunday, February 12th, 2012 AT 6:41 PM
JACOBANDNICKOLAS
MECHANIC
109,758 POSTS
It sounds like there may be a short in the brake light wiring. Usually, if there is a problem with a loose belt or weak alt, the problem will not be limited to only the brake lights.
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Sunday, February 12th, 2012 AT 9:14 PM
SATURNTECH9
MECHANIC
30,869 POSTS
You will need a multimeter to check grounds etc.I would make sure the brake lights have a good ground. Also that the alternator case has a good ground.