Battery runs down next day when the car is not used much in the previous 24 hours
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C Class W203
Battery runs down next day when the car is not used much in the previous 24 hours
The initial battery was observed to be running down, so a new 100AH battery was used to replace the MB battery which the electrician reported dead. But, even with the new battery, if the car is not used extensively within 24 hours, there's a possibility that the next day it wouldn't start & the check engine light is up presently. It's suspected that something's draining the battery, any idea what it could be please?
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From: Kitchener Ontario
1972 & 1973 350SL 1973 Bronco
Try disconnecting the negative terminal and check for an ark. Could have an open diode in the Alternator bleeding back. Or a power draw from an accessory like an aftermarket amp etc. Dave
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C Class W203
As regards aftermarket, didn't get it brand new, but the only change has been the condenser which was observed to be leaking after a jam by some driver. I guess the issue was observed sometime after that change. Like I stated earlier, the battery was also replaced.
Prior to the battery change, the check engine light was on and sometimes on starting the car in the morning, there's some stuttering sound which dies down after the engine runs for a little while. From scanning, it read P0301, a later scan read P0301 & P0302. On connecting the new battery, the drive was smooth & the response was very much improved and the early morning stuttering was gone. The check engine light was cleared and didn't return until now.
Any further hint would be appreciated.
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From: Worcestershire UK
W124 260E
They will arc anyway .Anything conected to the battery , clock, computer, alarm, all come alive when puting battery leads back on .Also the arc, or spark, from the battery leads can cause explosion . Bad idea.. Do you lock the car after use in the grage ? This will shut down the computers and save the battery . Other battery drain is alternator regulator .Some are replacable items .Do you see a no charge on the dash information .
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C Class W203
@Optimusprimem1, there's no "NO CHARGE" on the dashboard, took the car for a test and everything checked out fine, alternator & battery, I've also got a small tester which I used earlier & result was positive.
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C320
http://www.benzworld.org/forums/w203...ower-seat.html
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From: East Bay, Bay Area
2002 C32, 2012 S550
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C Class W203
@Optimusprimem1, the car is parked just outside the front door, not in a garage & it's locked at night.
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C Class W203
Thanks guys, I don't have the car around always but my wife does everyday .... I'd be around & would have this looked at over the weekend & give a feedback afterwards.
Note: The power seat on the driver's side ain't functional at the moment, but the passenger's side is fine ....
Note: The power seat on the driver's side ain't functional at the moment, but the passenger's side is fine ....
Last edited by CatalystW203; May 25, 2017 at 04:28 AM.
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S203
try to measure drawn current when car is locked. acceptable values are in the 50-60 mA range if i recall correctly. also IF you have an alarm remember some of them kick in fully after 2-3 mins. if current is too high try pulling fuses one by one and see if there are any changes
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C Class W203
My head's popping on this, almost .... I actually got a replacement SAM, not brand new though, couldn't get the wiper hook off (my bad) to swap it myself, so I decided to take it to a workshop to have it changed. So we decide to let the guy in the workshop run his diagnosis first & he says, "there's a short on your rear brake light" I knew that the rear brake light, left, was out, it was indicating on the dashboard already but that wouldn't be the reason the battery would drain, he looked through his scan tool again & mentions CAN bus, I then explained to him further the experience we've had & also that I had a replacement for the SAM, he says "your SAM is fine", I insisted show me what's wrong & he tells me, "you ain't a pro, let me do my job" after a series of discussions, he has the rug on the driver's side loosened, exposes that connector & says that's the bad guy .... He's yet to replace it but I'm trying to ensure the right thing is done .... That's why I need to know if this connector can cause a battery drain anyhow ....
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S203
well, in my w203 (which is European market, year 2002, M271) brake lights are powered via no 62 fuse, 5A, but i'm not sure whether yours is the same. the photo of the connector is out of focus and i can't see much but check for "burns" i.e. charcoal like areas that can cause a short. if that's the case and your brake lights are powered via CANBUS the guy in the workshop might be on to something. inside the dashboard as you open the driver's door you should find a "fuse chart". see if your brake lights are supplied by a fuse or "electronic" i.e. CANBUS. But why don't you let the guy replace the "culprit"? if the problem is still there it's on him to look further
Last edited by playfair; Jul 4, 2017 at 06:31 AM.
