tvg001

iTrader: (1)

this morning i turned on my car and drove it out of my house and i notice that the brake light in the dashbord turned on and then the air bag i notice that the battery was at 18volts i just went back and parked it i tried turning it off and on but its still the same any one know what could it be bad battery or alternator

MeentSS02

iTrader: (11)

Alternator would be the first place I'd look...check the small wire (the exciter wire, not the power wire) that runs into the top of it for any breaks. You might just want to pull it and have it tested if you don't find anything obvious.

tvg001

iTrader: (1)

thanks ill do that

wssix99

iTrader: (5)

Its theoretically impossible for the "battery" to get much above 13.2 V. Anything above that in the system would probably be coming from a bad voltage regulator in your alternator.

Turn on the power to the car but don't crank the engine. The gauge will then show you the battery voltage. When the engine is running, you see the combined effect of the running alternator hooked up to the battery.

tvg001

iTrader: (1)

it was the alternator it failed as soon as they test it good thing my buddy had bought one a while back with lifetime warranty so we just took it ant they exchanged it saved my self 170 dollars lol but it also messed up my battery the acid got cooked

samson_420

iTrader: (1)

Ouch, usually the alternators in our cars croak. Specially the rebuilt crap. But, that sucks at least it didn't damage anything major.