Battery Light - BMW Forum

92_325i · 12-14-2004, 08:17 PM

so today on my way to work, my battery light decided that it wanted to flash on and off. it kind off decided on what gear and rpm's i was at. it would be on at anything under 2000rpm, and a little higher in 4th and 5th. but also, sometimes it wouldnt be on when i stopped. i'm wondering if i should get a new alternator or something. the battery is 6months old so that's not bad. i dont know the history of the alternator as i've only had the car for 2months. so here's all the details: 20degrees outside. a little bit of snow on the ground, i let the car warm up for 10minutes before driving to work. about 15minutes after beginning my trip to work, the light starts to flicker on and off. the radio, rear defroster, headlights and parking lights were on, and the heater was on high. gas was at a touch over and eight tank. battery light came on and i shut everything off except the headlights. the problem persisted. the problem persisted after work as well. i drove to class and to the store and to get gas then. the problem persisted. however, leaving the store the problem was less seen, and then stopped. after that stopped, the ABS light came on for about 15seconds when i shut off the car to get gas. put gas in, and went on my way. ABS light was off, but the battery light was back to its antics. the car was also acting like it didnt want to start for a second when i was leaving the gas station. i think that's everything.
the car: a 1992 325i 5spd, 153k on the clock.
should i just buy the alternator??

Furious · 12-15-2004, 01:43 AM

well when the the light is on, have you tried testing the charge? could be the alternator.

xxxbimmer · 12-15-2004, 01:57 AM

I would say its the alternator.......I had the same problem last year

diezel99 · 12-15-2004, 07:10 AM

Definitively sounds like the alternator.....same problem last year.....give it a couple of days and slowly your whole electrical system will slowly quit.....and then everything will get dim and the guages will quit and then you will loose power and a couple of miles later.........dead

ghead

93 325i · 12-15-2004, 08:14 AM

I'd also say it's the alternator. Your at the same mileage when mine went on my first E36. Same symptoms too. I wouldn't drive it until you get the new alternator in. You WILL soon be stranded somewhere..

92_325i · 12-15-2004, 08:46 PM

well, everything did die today. fortunately for me, it happened right next door to work. i was lucky enough to make it to the parking lot with it where it will be sitting until friday and i get the daylight to fix it there. does any one have any suggestions about where to get a new alternator? i have the Bosch one.

bigred318 · 12-15-2004, 11:03 PM

ive had the problem 2 times in t2o years, alternator. take it out and go get it bench tested for free at shucks. they will tell ya if you need a new one or not, better to take the time now to get it tested and take it out and put it back in ,rather then have the car die in an intersection (cough me) so yeah DO IT! haha if you need help getting the alt in our out (in theres a few tricks... that make it go easier) let me know ive defintaly done this a few times!

David

92_325i · 12-17-2004, 10:01 AM

well i've been calling around and getting prices, and it seems that i have a choice between an 80amp or 140amp. anyone know what the stock alternator is rated at? i'd like to replace it with the same, but i'm not sure which i have. i have the Bosch alternator.

BigRed318 - any tips you can give me would be great. not looking forward to doing this in a parking lot in the 25degrees of coldness outside. lucky me.

93 325i · 12-17-2004, 10:07 AM

My BMW manual sates:

80amp- Manual Tranny
140amp- Auto Tranny

So in your case 80amp. Double check on the alterantor that you are replacing, it will tell you right on it.

92_325i · 12-17-2004, 10:32 AM

awesome. thanks. i'm going to go order one then. thanks again.

93 325i · 12-17-2004, 10:34 AM

no prob..goodluck changing that ish in the cold! thats gonna suck

92_325i · 12-17-2004, 10:38 AM

eh...i'm used to it. last winter i did an engine swap on my 240sx in 40degrees. plus a bunch of body work as well. i guess i'm just dedicated - or too cheap to pay someone else to do it...

92_325i · 12-18-2004, 01:45 PM

so i did the alternator today. 35degrees out, with 10-15mph winds. yay. no snow tho, so that was a plus. got dropped off at my car, which was 20miles from home. took a limited amount of tools because i could only carry so much. it ended up taking me 4 hours because of two complications of not having the right tools.

ghead: needless to say, i am freezing, but happy. i think my car is happy now too.