SL/R107: 1980 SL 450 Battery Problems "HELP!
05-09-2011, 08:55 AM
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SL450
1980 SL 450 Battery Problems "HELP!
My Battery goes dead after sitting for only a week . The repair shop says this is normal for this type of Mercedes and then wanted to know if I wanted to put in a Tricle Charger on .
Is this normal ?
Is this normal ?
05-09-2011, 08:13 PM
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82 380SL 96 SL500
Off the top of my head, one of the prime locations for problems lies in the radio and antenna circuit. I can't recall any of the other locations I've heard of.
However, checking current drain through all the fuses will tell you the general circuit causing your problems.
A good start will be looking at the wiring diagrams in the service manual. Here's a link to an online copy.
http://www.startekinfo.com/StarTek/o...tedDocId=11883
05-09-2011, 08:23 PM
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1988 260e
even pros don't always know and are too afraid to say i don't know. i had a problem with batt going dead after a couple of days and got all kinds of stories until i figured out that with meter there was a drain on batt even after key was off by diconecting cable to batt and seeing the drop or gain on batt. there was a drops on batt os i started looking and found the glove box was out of adjustment and light was staying on but i couldn't see it when closed.suggest getting in completly dark place and see if there is any light coming from engine, trunk, glove or dash compartment when key is off.
06-02-2011, 10:38 AM
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'87 500SL '99 CLK230K 05 JEEP Grand Cherokee
It's not rocket science, it's simple electrics! But primary areas to look at are where the power is not cut off when you remove the key. Off the top of my head:
CLOCK
Interior lights
Alarm (will normally drain around 10-20mA as I recall).
Of course wou will need a meter to check.
If you have a good, fully charged 80Ah battery, to drain it in a week (168hrs) will take around 80/168A or approx 476mA. So the area you need to focus on should be fairly obvious when you meter it (if you meter for instance 200mA, that would be a suspect area). Once you know which circuit it is, you then have to isolate to the root cause, which may or may not be a heap of frustrating back breaking work!
CLOCK
Interior lights
Alarm (will normally drain around 10-20mA as I recall).
Of course wou will need a meter to check.
If you have a good, fully charged 80Ah battery, to drain it in a week (168hrs) will take around 80/168A or approx 476mA. So the area you need to focus on should be fairly obvious when you meter it (if you meter for instance 200mA, that would be a suspect area). Once you know which circuit it is, you then have to isolate to the root cause, which may or may not be a heap of frustrating back breaking work!
