Battery voltage at idle.

antiv6

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When my car is off the battery reads 12.7 and when I turn it on it stays at around 13.65 just testing it in a parking lot with a volt meter. Every once in a while my gauge cluster flickers for a second. Are these normal numbers for a battery/alternator or is something on the way out? Battery is only a couple years old.
 

03cobra#694

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Car off.
017a.jpg

Car running.
18a.jpg
 

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Totally dependant on temp outside and if the car is heat soaked. 12.7 with car off is normal for a good battery. 14.2-14.3 on a cold start while idling and running for the first few miles. Drops to 13.5-13.7 running on a warm/hot day after becoming heat soaked. A little higher if it's cold outside.

Edit: I've seen mine at idle drop to 12.9-13.1 at idle if its hot outside and the car is heat soaked. As soon as I give it throttle to take off it jumps back up to mid 13's.
 
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antiv6

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Just went a did a cold start test and it was 14.4 which is good, now I just don't know why my gauge cluster flickers at times.
 

Nate14120

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Sounds like the cluster illumination could be going bad. Mine flickered and worked some days and not others before going dark.

There is a fix in the how to section but the speedhut inverter was discontinued. The replacent inverter isn't quite tried and true yet.
 

hotcobra03

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Check ground wire's on radiator support next to battery..

I had found ground from battery to support burned inside casing..

Made dash go nuts..flicker and gage sweeps..
 

antiv6

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The battery light kept coming on then stayed on today so it must be the alternator was on its way out.
 

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