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Discussion Starter · #1 ·
SO I was driving around town with my friend when we noticed that my voltage meter on the gauge cluster was rather high. The blue line is where it is all the time. Fog lights on and everything. I have an aftermarket flip out Navi that powers up my iPod and it still sits that high. Is that good or bad? (I didn't feel like going out and taking a picture so I just drew it, much faster for me, haha.)

 

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hi, i would & i did go to auto zone & bought a volt meter.
it was around $15. all other's that had a digital reading
were around 30+.
it will tell you exactly what you have.
check it with the truck off. & check it with the truck on. by touching the red to the postive, & the black to the negitive. put the setting on 20. that will allow you to see .50 or 14.50 the tenth's.

i'm sure some have gone bad by going way up.
usually the don't put out enough.
which will not charge your battery.

but that graphic seems to be way up high.
if it is in the middle on my tundra dead in the middle it read's 14, if i 1st start it up it goes up sometimes to 14.1 to 14.2 on my scangauge2. but when the truck is charged for some reason the truck doesn't need all that so it drop's. which makes the alternator work less, prolonging it's life.
i belive this is what denso has done to there alternators.
i honsestly don't know how.

i would either go have it checked out by a pro, or buy that volt meter.
it's good you asked the question here.
i wonder myself if it's reading what yours shows, approx 16ish to 17.50
if thats really bad. and could burn out something.
good luck,
gorilla
 

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I had a similar issue whereby my battery voltage was low around 10.5 volts and had difficultly starting if left for a few days without usage. When it did start, the voltage on the battery would go up to 22 volts for a few minutes on my voltmeter before it dropped back down to 13.5 volts.

Thinking the voltage regulator within the alternator should always keep it at 12-14 volts, I asked a shop that rebuilds alternators. They checked it out and stated that my alternator was good and that a dead cell within my battery was probably the culprit. Apparently, the voltage regulator will not regulate when too much current is being drawn from the alternator.

I replaced my original battery, being 7 years old, and the problem went away immediately. Never owning a battery that lasted more than 3 years was new to me and I've been told by others you shouldn't keep a battery beyond 4 years on average to avoid these type of issues.

By the way, high voltage out of the battery is never a good thing since any voltage clamping circuits on your ECU and other electronic parts are constantly being stressed.

Hope this is helpful.
 

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Sounds like you have either a bad alternator or bad battery. An alternator that puts out too much voltage will ruin a battery by over charging it, boiling the acid out. Go to an auto parts store and have them check both your battery and alternator. My money is on the battery being bad, but till you check it out, you'll never know.
 
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