Voltage reading from SG

[The Spectacle]

Can anyone with a SG go out and tell me what voltage numbers they are seeing on it? My car won't hit 14v while running no matter what I'm doing or what accessories are on...it usually hovers around 13.7-13.8v which I know is not bad, but seems weird. The lowest it hits is 12.9v with my audio system at full tilt, AC on full blast and all the lights on. I am not experiencing any voltage related problems with the car, just curious as to why this is.

[Tamago]

13.8V is normal

[marcus]

13.8 is average..

[The Spectacle]

My other car, with HID's on, AC and stereo, hovers around 14.1v. With nothing on, it maxes out around 14.5v. I thought that was average.

[eTiMaGo]

what car is it? maybe it's just a different alternator specification... a few 10ths of a volt less should not hurt anything, I mean, most equipment has to run at 12V anyway...

I see 13.6-13.8 pretty much all along when the engine's running...

[The Architect]

If im driving during the day without lights on and the system on it varies between 14.17-14.23

with HIDS as well on its at about 13.8-14.0

I dont use A/C almost ever.

[talnlnky]

right when you start your car you should see it hit 14v... The Alt's goal is to make sure the battery is always fully charged to 12.5V, and in order to charge you have to have a higher voltage than the battery, higher the voltage, and amperage, and the quicker the charge will be. your car DOESN'T need to reach 14V, but it does sound a bit weird that yours does not. It might have something to do with the temperature outside, but I'd think you'd see higher discharges and charging voltages in the winter than the summer.


I dunno

I see 14-14.2 on mine every day for the first ten minutes of the drive. Do you do highway driving much? If i'm doing low RPM's your voltage won't be as high... there's times when i'll see a .5V difference just by changing gear(rpm's).


I wouldn't worry about it too much until you never see a voltage higher than 12v

[nth09]

Mine is 13.0 or 13.1 when full engine is running and my ICE turned on. My battery is stock. Is this normal?

[The Spectacle]

Update from the dead.

Stock battery died yesterday. Replaced it with Stinger SPP 1200 and did the big 3 upgrade but still seeing less than 14v @ idle with nothing running. Measures between 13.2 - 13.7 @ the alternator. Anyone have any idea what the stock alternator is rated for?

[Brian]

13.2-14.8 @2000 rpm is normal. Stock alternator is 80 amps.

[The Spectacle]

Did you mean 13.8?

[Brian]

No. Factory repair manual says 14.8

[The Spectacle]

I have NEVER seen higher than 14.1 in my 3 years of owning this car. Even then it was for a brief 1-3 seconds

[yarisugi]

same here. Only in the 13.x range - at 13.0 (sometimes to 12.9) car starts doing a little shake until it goes back up again.

[mazilla]

I am almost always between 13.9-14.1, I'm running a re-wound 120amp alternator.

[Revsson]

Does the OBDII connector read the actual battery voltage? :iono:
Perhaps CTScott can answer when he gets back from California?

[bzinn 1]

i get 13.4 on average that is with fogs and lights on.....stereo usually eats off another .2 off that for me.

[The Spectacle]

Does the OBDII connector read the actual battery voltage? :iono:
Perhaps CTScott can answer when he gets back from California?

Yes. I've verified this with a multi-meter...its within .1 of what you read at the battery and/or alternator

[fnkngrv]

are you running an underdrive pulley?

[The Spectacle]

No

[mo_feezy]

I have a less than 6 month old battery in mine. I checked yesterday. I was getting 13.7 with everything off (while driving), 13.6 with AC running, and then fluctuating between 13.5 and 13.6 with the AC and the system (about 600 watts or so). Idle voltages are similar, never dropping below 13.3 and never getting higher than 13.7 really.

[MGargano]

I've been having the exact same issues/voltage readings as The Spectacle.

I did the Big 3 upgrade and saw no change. I swapped the alternator, no change. I disconnected all extras (HIDs, sound system, radar detector, etc), no change. I even went so far as to have NST custom build me a 20% overdrive alternator pulley for $150, but I ended up not putting it on and just living with the low voltage