wanna see if i did just kill my batt..accidently left music playing in it for 4 hours. was working on it when i got a call that my bro had hit his head snowboarding and blacked out. he was ok and awake at ski patrol but my parents were out of town so i dropped everything and got in the mustang and picked him up and took him to urgent care. he just had a slight concussion and my parents got there about 2 hours later so they brought him home. but the music had been on the whole time and since that night, my battery level drops to 9 if im under 2000rpms and the check gauges light comes on.

so tonight it rained and froze so the streets were solid ice. well my mustang slid everywhere and i turned around and got the jeep. had to take my gf home. the new KM2s are amazing btw! but either way i was leaving the neighborhood when the dash got very dim..voltage dropped, and no matter what rpm, stayed dropped. so i took my parents car. so is this the battery or does it sound like maybe alternator? im thinking battery. ill check connections tomorrow too

thanks!

 

im guessing but check ur alternator

 

Yup, alternator. Take it off and get it checked.

If it was good your voltage would stay up while it was running.

 

yeah ive had an alternator go out before but the battery voltage would stay down. this time though the voltage would go up with rpms so i dont know. the newest alternator is about 6 months old and the battery is about a year old

 

you should have a warranty on your alt. if it is that new.

 

I would still vote that it may be your alternator. Just remember that when one goes bad it can cause the other to go bad too. If you have a voltage meter you can take the positive and put it on the main power out on the back of the alternator and then ground the other on a piece of metal; Or, you can take both the battery and alternator to an autozone and have them tested. If I was in this situation, I would pull the alternator and the battery and have them both tested. (Because I don't have a voltage meter) Good Luck and keep us posted!