GXPPOWER

when i urn the car off and just put the keys on run or whatever and it shows all the reading. the battery charge is way down in the hazard. this was happening on my old battery also. ive had this one for mabe a year now a autozone platinum or whatever. i never noticed it but one day my grand father said my lights were dimming alot when i was starting up one morning.

i mean evidently the battery is being charged some or it would have been dead a while back. what ways can i check that the alternator is working at 100%?

i went once before to advance auo and they ran a alternator check and said it was fine. but again hats been a while.

SladeX

while the car is running, test the voltage across the battery, if it is charging properly, the voltmeter should read 14V.

Drive it around, let the car warm up and heat soak every part of the engine bay. Make sure lights are on, car is running, toss in the defroster and fog lights, radio etc. Does it still read 14V? If your alternator is working fine, there should be no instance it has to draw power from the battery and should read at or around 14V. If it ever goes to 12V or less, you are running off battery.

GXPPOWER

so do i take the volt meter and just match the end up with the positive and negative terminals?

SparkyJJO

iTrader: (11)

Yes..

eallanboggs

iTrader: (1)

You can match either end of you meter terminals to the battery posts as long as you're using a DVOM and not your grandfathers Simpson. DVOMs are very forgiving if you get the polarity wrong(it will just give you a negative value, but it will be numerically correct). Grandpaws Simpson probably won't be so forgiving if you hook it up backwards and Grandad will be mad at you for a very long time if you fry his Simpson which he has had for over 50 years until you got your hands on it. Don't use Grandpaws Simpson unless you know something about polarity in DC circuits. It takes over 12 volts to charge a 12 VDC battery. Do as you have already been told and turn "ON" all your electrical devices(loads) and take a reading. It should be over 12 VDC fully loaded. 14 VDC would be nice, but I'd settle for 13.5 VDC.

GXPPOWER

got 14v dead on. steady as can be. with radio going, AC,and lights on

WS6store.com

iTrader: (30)

I've seen voltage at 14 volts with all loads on, but then when you load test the system it falls flat on its face. Have the alternator load tested...that will be the determining factor. It should be putting out around 100 amps at 1500 rpm under load.