pyrojeff

Alright, I was driving back to school tonight and all of a sudden my battery light goes on while sitting at a stoplight. The entire day I sort of noticed that my lights in the dash were slightly lighter. But now when the battery light turned on, I could definitely tell the dash lights were almost off.

A little while later, everything in the car becomes dim, including headlights and stuff. The spedometer and tachometer just fell to zero, although they would occasionally jerk upwards to where the needle should be but then drop back to zero just as fast.

Once I get into the school's parking lot, I figured my car wouldn't start up. So I turn it off, pop the hood and make sure all the battery terminals and other things are connected, and then try starting the car up again. All of the lights in the dash are as bright as they should be, but once I start cranking the car, all the lights almost turn off and the car gives up on cranking.

Does this mean the alternator is dead? If so I'm pretty much screwed.

21tgs

No cranking is a dead battery. In this case it sounds like the battery is drained because you drove to school on battery power. You drove on battery power because your alternator died.

To verify all of this have someone jump start your car. Once your car is running, and after you disconnect the donor car, use a volt meter across the battery terminals of your car and take a reading. A good alternator will be holding around 14 - 14.5 VDC.

Your dashboard lights work because they use a minimal amount of power. Unlike your starter which uses a ot of power. Something that your battery is short on at the moment.

hondadude

When you get the car started you can try tapping on the top of the ALT to see if the batt light goes off. If the light turns off cause you jarred loose the brushes, you can consider just replacing the brush pak. The dealer will have the brush pak for around $25.

pyrojeff

Thanks for the help guys, although I haven't gotten to try any of your guys' advice. However, I tried starting up the car today, and it started up just fine. I was afraid the car might get stuck somewhere so I didn't even bother driving it.

Is it possible to drive with a bad alternator? I figure once the alternator dies, the car's electronics run off the battery, so is it possible for the car to just run off the battery? I'm guessing it's a no, since the ECU is powered electronically and without that the engine would just die.

Thanks in advance for the input.

lilman4o8

i don't know i'm really right, but the battery is just needed to start up the car, once the car is started you can pull out the battery, but a dead altenator won't recharge the battery to start it up again, so i'm not really sure, you should get the battery checked and chagne the altenator if it's a bad one, you're going to have to anyways

pyrojeff

Yeah I know, it's just a matter of moving my car from the campus parking lot to my house thats 20 miles away (I really don't want to work on the car in the parking lot). So I was just wondering if I could get home fine as long as the car starts up.

JimBlake

If it's intermittent, you might start it up, measure 14v at the battery, go for it.

But if you start it up, measure 12v or less at the battery, then the alternator isn't charging. Then I wouldn't trust it to go 20 miles.

If you really really gotta take it home, have someone follow you with jumper cables. Hook up your voltmeter to the cigarette lighter or something, when it gets below 10 pull into a parking lot. Hook up the jumper cables, let your friends car run so it charges your battery. Maybe you'll have to do this 1 or 2 times??

fleetmack

i drove mine after the alt crashed so i wouldn't have to tow it to a friend's garage! i drove it about 40 miles....

dont use the headlights, turn off the stereo -- basically avoid using EVERYTHING electric that you possibly can, as it all eats up battery power.

pyrojeff

Well I finally got it home. The car stopped about 2 miles before my house, but my friend just jumped it and then I got it home fine. Damn, almost got it there without having it jumped.

Anyways, thanks guys for helping out.