Volt Gauge question
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
Volt Gauge question
My volt gauge needle is flickering back and forth between the 3rd and 4th hash marks on the gauge (the needle more on the higher side). And when it does that, the backlights on all the instrumentation get brighter and dimmer in sync with the flickering on the gauge. It's almost like I am moving the dimmer switch up and down really fast, but it's VERY faint. Hardly noticeable until you look closely. What could be causing this? I don't wana get a short or something. Is this something I should worry about? The digital gauge I think said 14.6 volts as average.
Last edited by CStewTAMU; Jan 3, 2008 at 10:34 AM.
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
Glad this alternator will be super easy to change-at least it looks like it would be assuming that's where it is located. It doesn't always do it. All readings are withing normal ranges too.
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
I took it to OReily's and the guy checked my battery and said it was a little low (don't even get my started on electronics-I know less than nothing) and that it looked like a "Walmart" battery which in his opinion wasn't very good. (I just bought this car 2 weeks ago BTW). He said the alternator was fine.
Race Director
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From: Rolla Missouri
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Just so you know. Your voltage gauge flickering is not what's causing your dash lights to go dimmer and brighter. It's the other way around.
The volt gauge is just reading voltage. When the voltage is changing (dash backlights getting dimmer and/or brighter) the voltage gauge resisters this by moving the needle either up or down depending on the current voltage reading.
You could have a short, or bad ground.
Could be a bad alternator (but you said they tested that).
A low battery could also cause this, or maybe a loose battery connection.
The volt gauge is just reading voltage. When the voltage is changing (dash backlights getting dimmer and/or brighter) the voltage gauge resisters this by moving the needle either up or down depending on the current voltage reading.
You could have a short, or bad ground.
Could be a bad alternator (but you said they tested that).
A low battery could also cause this, or maybe a loose battery connection.
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
Battery connections are good. Hopefully this is just a fuse. Which fuse is for the instrumentation?
I am know less than nothing about electronics. I wouldn't know the difference between a volt and an amp or a ground wire vs a barbed wire.
I am know less than nothing about electronics. I wouldn't know the difference between a volt and an amp or a ground wire vs a barbed wire.
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Engine running, unplug the alternator and observe if the flickering stops. If it stops, your alternator is showing its age and condition and only if it bothers you, replace the alternator.
It cannot be due to a short, shorts blow fuses. Only one circuit in your car is not fused, that is the starter motor large wire.
Parts stores usually cannot determine if the alternator voltage regulator is jiggling the output voltage.
Engine running, unplug the alternator and observe if the flickering stops. If it stops, your alternator is showing its age and condition and only if it bothers you, replace the alternator.
It cannot be due to a short, shorts blow fuses. Only one circuit in your car is not fused, that is the starter motor large wire.
Parts stores usually cannot determine if the alternator voltage regulator is jiggling the output voltage.