The temperatures just dropped to the low 20s, and after sitting over night, my 88 300 SEL won't turn over. It seemed like it almost had enough to go, but then it just drained the battery real quick and now it's down to about 7.5 volts and dropping slowly. I recently replaced alternator and battery last month. I jumped the car and the alternator is putting out about 13.75 volts when running. Any ideas?? Also, I noticed that a light an indicator light is coming on mainly when i press the brake. It is orange and to the left of the steering wheel.. it's a circle with dotted lines around 2 sides of it. I don't have a manual so i don't know what this light means. Thanx for all your input!

I would do a search here for battery drain. Perhaps something is staying on when everything is supposed to be off. you might pull fuses and see if you can't use a multimeter to figure out who's the greedy one. Don't know what that indicator light is...

cdt

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2002suzukiGSF600S
1985 190e 2.3

ok, couple of things. has he checked the water in the battery, if so does it need topping up (deionised water of course) and the idicator light means that the brake pads are low

thanks a lot for responding so quick guys! I think u are right about the draining thing..cause i took off the negative cable and tested the battery and immediately the volts starting climbing. It's a brand new battery so i hope the water levels are good, though i haven't checked them..

ps..any idea if that light means rear or front brakes..?

i'm kind of a novice when it comes to electric..i can read the meters..and i have a multitester...but can u explain how to test for a drain...thanx again.

cant help u with the battery, but the brake pad indicators are on the front brakes, never heard of them on the rears. have u tried the multimeter on the battery when the ignition is off, but the battery is still connected. check to see if the voltage is constant. if not then obviously something is staying on?

i'm kind of a novice when it comes to electric..i can read the meters..and i have a multitester...but can u explain how to test for a drain...thanx again.

thanks for the info about the brakes...greatly appreciated!

i did test the battery with the terminals connected and it's definetely draining...just have to figure out what it could be now..could it have been something that's been draining for a while but just got significantly worse with the low temps?..i can't figure out why all of a sudden it would start doing this..

read my post, i wish i knew why mine was playing up, and why it happened suddenly. welcome to the world of mecedes it seems

WOW!..it's freaking cold out! Okay ...so i've been testing fuses ..i'm happy to be back inside thawing out in front of my computer screen. i found three fuses that are hot with the car off and key out of ignition...i pulled one...#1 Fuse, Auxiliary fan..and the battery was still draining..then i pulled #2..diagnostic term. 6, hazard warning system, clock, front roof light, electronic radio, vanity mirror light, electronic illumination control. ..and the battery started charging again!...so i guess that's where the problem lies..

also, i installed a radio myself about 3-4 months ago..and given the inferior electrical knowledge i possess..i'd say that's probably it...any suggestions where i could get this problem fixed?...or a diy solution?

hmm, if the radio is connected in through din blocks, then its unlikely that that is the cause. if it is not, is it possible that you might have connected the constant 12v feed to something on the radio other than the proper wire? best way is to unplug the radio, replace the fuse and check your voltage again. cant hurt?

okay...well it turns out, it's not the radio...but it's something on that #2 fuse..it's not draining any power once i take out that fuse..but as soon as i put it in the volts drop to 6 and keep going...i guess there's a short somewhere there. the fuse blew the other day and i put a new one in, but it looks like there is some residue around it from that blown fuse. i'm thinking maybe once it blew it shorted something out on that line. once again, that fuse supplies power to the following:

diagnostic term. 6, hazard warning system, clock, front roof light, electronic radio, vanity mirror light, electronic illumination control

and i cut the two hot wires to the radio and put the fuse back in and the volts still dropped. the only thing that seems to be working is to keep it out completely. do u know if there is a reset button anywhere..? you've been real helpful ..thanks again.

I am not an expert but you say that the vanity mirror light is connected to this fuse. it seems to me that that light is one of the lights that when closed you cannort surely confirm if it is really off? I'd start there now and see what happens?

Iggy

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Insanity: doing the same thing over and over again and expecting different results.

2006 - Suzuki Gran Vitara (2.0 L fully equipped) Like this car so far except for trying to put on the seatbelt.
1988 - 190e - 2.3L - 172K miles (It now belongs to the exwife)
1999 - Chevy Blazer LS Fully Equiped - killed it June 2006
2001 - Honda Civic EX - 68K miles (sold June 2004)
1963 - 220S - Dual Carb 6 cyl. (sold)
1994 - Yamaha WaveRaider (fun to ride)