What should the voltage be?

hitbyastick · 04-20-2006, 08:30 PM

Hello,
at idle my voltmeter reads 14 volts at the factory connection for the center console. When I step on the brakes and the stoplights turn on, it goes down to about 12.2 or so. If I then turn on the headlights and all that, it goes down to approximately 10.5. If I add a turnsignal it falls slight below 9.
If I remember correctly, the car has always down this. Although I could be wrong, the car has been sitting for a while. The thing is that the lights don't dim or any of that nature. Faulty gauge? Regulator? Or maybe the alternator is not up to par?

666 · 04-20-2006, 09:19 PM

German engineering.

It's fine.

Joe Bob · Joe Bob's Garage

30 year old gauges are at best....a wild a$$ guess.

Using a voltmeter/Fluke/Multimeter reading at the terminals a FULLY charged battery.

12.5v at rest
13.0 at idle
13.5-14.5 at 2500 rpms
Anything more than that....you'll end up cooking the battery as the volt regulator is likely bad.

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Like the above two guys said, it's normal. I figure the voltmeter is mostly there for entertainment, not to show the health of the charging system.

If it starts behaving differently than it always has in the past, then it could be showing a problem. But otherwise, don't worry about it.

--DD

hitbyastick · 04-21-2006, 10:20 AM

First good news about this car all year!

Joe Bob · Joe Bob's Garage

The fact that you have a running 914 AND in Germany is a PLUS....

vesnyder · vesnyder's Garage

I agree with Dave. I've installed voltmeters in my 914 and 911 and in both cases they read above 14 volts - with my 914 running close to 16. In the 911, when I turn everything on - radio, fog lights, brights, etc - it goes down to 12V. Don't have that much electrical stuff in the 914, so it does not vary that much.

Jbagel2 · 04-22-2006, 01:20 AM

do you ever have a hard time getting the car started? thinking mabey you have a corroded ground strap, 9V is an pretty low drop, 14V isn't to bad a lot of newer cars actually charge at about 14.4V. mabey try makeing a new ground for the gauge somewhere close to the gauge and see if that helps. Just a suggestion.