Help in Battery Voltage ?

Nickname · Post by **Nickname** » Fri Jan 16, 2004 12:50 am

Hi, can any one help me ? coz when I drive my car recently, I find the voltage will get over 14V, when I stop, it goes back below 14V, is my car have trouble ??? what's wrong is it ?? is it harmful to my car ?

MADFTO · Post by **MADFTO** » Fri Jan 16, 2004 9:22 am

I don't believe that would be causing problems, however, how far is is dropping below 14?

Little changes will occur during driving, depending on the equipment you've got active at a given time, but there should be any sudden drops from say 14v -> below 12v.

So I wouldn't worry about it if it's just changing above and below 14V.

Do this as an indicator of what happens.

While idling, watch the voltmeter when you turn on the headlights, then turn on the indicators, the volts should change as the lights go on and off. it should only move a mm or two.

Nickname · Post by **Nickname** » Fri Jan 16, 2004 11:14 am

It's luckly that my car's voltage didn't drop below 12V, what I worry now isn't not enough voltage, but a over voltage.
My car seems charging up to 15V (sometimes), so I'm worry will it damage to my car's product !! or is my car got problem charing up to 15V ?

MADFTO · Post by **MADFTO** » Fri Jan 16, 2004 11:23 am

I usually run around the 14V mark.
Well I don't know what the accepted range is, but 13-14V is the standard in my mind.

Best person to ask is an auto-electrician.

I don't see that there would be a problem with it, chemical batteries can stand a bit of pounding, and you must remember that not all the current is going to the battery, most of it is being used by the engine.

ruchi · Post by **ruchi** » Fri Jan 16, 2004 11:25 am

Are you basing these figures off the volt meter in the centre console or are you using test equipment such as a multimeter?

Raven · Post by **Raven** » Fri Jan 16, 2004 11:36 am

the fto's power when the car is running is 13.8 volts nominal i think. which is fine, if it didnt then the battery probably would not charge. and yes even i have seen mine say its higher then that, but unless its blowing fuses then i would not worry to much about it.

ruchi · Post by **ruchi** » Fri Jan 16, 2004 11:47 am

Fuses blow because of amperage, not voltage. Even if the car had 240v going through it the fuses still wouldn't blow until the amperage was too high. Everything else would fry though!

The voltage readings you get will vary depending upon the equipment used, where you are measuring the voltage, and whether it is under load or not. So these are the first questions that need to be answered.

Although a car's electrical system is said to be 12v, under normal load, it generally fluctuates between 10-14v, not under load it can go as high as 16v, depending upon where you are measuring it.

scracy · Post by **scracy** » Fri Jan 16, 2004 5:34 pm

I would expect the voltage to be around 13.8V at idle with little or no ancillary equipment, just over 12V with lights on. 15V seems awfully high to me (though i would expect the cars voltmeter to be inaccurate) If the true voltage at the battery with the car running is 15v i would suspect the alternators voltage regulator is buggered. Get it checked! Iam an electrician by trade and i have NEVER seen any cars electrical system without load produce 16Vdc! at least not one that didnt have a voltage regulator problem.

FTO338 · Post by **FTO338** » Fri Jan 16, 2004 9:06 pm

Raven & Scracy is right, i've got an Apexi RSM which can measure voltage, in the morning when u first started, it should read from 13.9-14.1v, once u warm it up, its around 13.6-13.8v!

The last time when i had a very high voltage, it was my alternator that playing up! so i suggest u get it check.

Nickname · Post by **Nickname** » Fri Jan 16, 2004 9:13 pm

I'm using the standard Voltmeter inside my FTO, I think it may be the problem of alternators voltage regulator is buggered to me.
Since I don't have much time and $ to fix it atm, so if I keep driving my car without fix it, will it coz any problem?? If I need to fix it, how much will it cost??
Thanks all you guy's help !!

ruchi · Post by **ruchi** » Fri Jan 16, 2004 9:27 pm

Do you notice any electrical issues, such as any lights getting brighter or dimming unexpectedly or the volt meter fluctuating.

Nickname · Post by **Nickname** » Sat Jan 17, 2004 2:59 am

Everthing in my car running normal, nothing special but only the voltage, but there has been happened once when I driving at nigth, I turned on my head light and then drive around 10 mins get to the petrol station ready to refill, then I turn off the light before turn off the engine, once I turn off the light when idling, the battery signal light start lights up a bit, but not fully lights up. Around 1 weeks later today, haven't see this happen again, too worry about my car !!

Raven · Post by **Raven** » Sat Jan 17, 2004 12:57 pm

1 thing you can check is if the headlights dim or get brighter when you rev the engine