maybe alternator??

[boostingsx98]

i have the brake light and battery light on when i start my car. But when i rev it past 2500 the brake and battery light will go out and as soon as it drops below 2500 it comes back on again. same thing applies when i am driving it. Is it a bad alternator or faulty connections? any ideas would be helpful....

 

[VETTE_50_TH]

Do your lights dim at all? If so, then its probably the battery. Quick test, take a multimeter to the positive of the alternator and negative to the body of the car(ground) and see what you get. Should be around 14V or so. And do the same for the battery. There shouldnt be a huge difference between the two while the car is running.

James

 

[boostingsx98]

well i just bought a new battery because i thought that could of been the problem but the lights did not go away....

 

[Butterfinger]

Hey the best way would be like said above with a multimeter. The second have autozone check the charging system at no cost. And if enable to do that start the car have all accesories off unplug the battery the alt should keep it running. this=ghetto/inaccurate test but can tell you if the alt is putting out.

 

[SeMi380]

start the car, unplug the negative battery terminal, if it turns off your alternator's bad.

 

[boostingsx98]

alright thanks. i checked it by unplugging the negative from the battery and was the alternator. replaced it now everything runs good! thanks for the help!

 

[Defiant]

start the car, unplug the negative battery terminal, if it turns off your alternator's bad.

No. Do NOT do this to any car later than 1985.