Voltage Regulator
- Thread starter nodemon
- Start date
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Not really.
The alt gauge measures Amps
The voltage regulator regulates the voltage going into the battery based on the load on the alternator.
So if you have a high load like the lights are on. The ammeter will read discharge then with the engine running the ammeter will read in the middle because the alternator is supplying just the amount of power the load needs.
If the ammeter is reading high then it is trying to power a high load between the ammeter and the battery or the battery itself.
I had a similar situation a week or so ago.
Turns out the battery was on its way out. Not saying that's your issue.
My symptoms were 10 amp charge current but the charge voltage was low like 13 volts.
The alt gauge measures Amps
The voltage regulator regulates the voltage going into the battery based on the load on the alternator.
So if you have a high load like the lights are on. The ammeter will read discharge then with the engine running the ammeter will read in the middle because the alternator is supplying just the amount of power the load needs.
If the ammeter is reading high then it is trying to power a high load between the ammeter and the battery or the battery itself.
I had a similar situation a week or so ago.
Turns out the battery was on its way out. Not saying that's your issue.
My symptoms were 10 amp charge current but the charge voltage was low like 13 volts.
Resting voltage on my battery is 12.3v.
I guess I'll keep searching out the issue.
Thanks for the response..!
So was mine. But would only charge to 13 and change but the ammeter was showing a 10 amp load with nothing but the engine running.
I put the battery on a charger till it went into trickle charge mode, took only an hour but the charging voltage was only going up to about 13 and change. The car would also only go to about 13 and change, but show 10 amps charge. 1st line right of center.
After I replaced the battery the car would go to about 14 and change but not show much on the ammeter
Both batteries had resting voltages in the 12s
Batteries have a built in resistance. As they age the resistance increases.
BU-902: How to Measure Internal Resistance.
At some point you can not put in enough current to over come the internal resistance.
This is my understanding of the basics of how it works.
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Airstream65
Well-Known Member
Airstream65
Well-Known Member
If you decide to replace your VR, DO NOT get a parts house VR! I went through 4 that were bad out of the box, I ended up getting a black Mopar performance one and it solved my under charging issues.
67Dart273
Well-Known Member
I don't understand your answer. Of course it can. One that for some reason is causing a "full field" (full charge) condition, and or a large capacity alternator, or an alternator that is recharging a somewhat dead battery and actually working normally.
I used to have an SW 100A ammeter in the old Landcruiser, SB Mopar, and for quite awhile had one of the old "big frame" 105A units on there. Two batteries and a winch. Yeh, you could bury that 100A meter!!! I think I had no6 wire in the charging circuit, and should have been larger
But monitoring VOLTAGE is the key. If the thing is running at normal charging voltage, and if the ammeter will not center eventually, you likely have a battery problem.
Do a little reading in the service manuals. There's a chart in most of them, showing voltage vs temperature. The other "go to" really popular problem, is voltage drop in the harness/ ground which can cause over-voltage, but that will not "bury" the needle.
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