Car battery drains over night
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Car battery drains over night
HELP HELP I have a mercedes 1986 300e New tune up new belt new battery
but over night the car is totally drained by the morning I read here the following
1)try to located the source of the battery drain. With the engine stopped, you should be able to isolate which circuit is active, using a multimeeter. Check it at the the fuse box.
2) Check all major grounds (battery cables)
JackD
The response was giving by JackD
part 1 I f I understand it is to use this device and check each fues correct ?
and part 2 how would I know which are all the major ground battery cables are they in any particular part or all over ?
HELP HELP HELP HELP
but over night the car is totally drained by the morning I read here the following
1)try to located the source of the battery drain. With the engine stopped, you should be able to isolate which circuit is active, using a multimeeter. Check it at the the fuse box.
2) Check all major grounds (battery cables)
JackD
The response was giving by JackD
part 1 I f I understand it is to use this device and check each fues correct ?
and part 2 how would I know which are all the major ground battery cables are they in any particular part or all over ?
HELP HELP HELP HELP
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From: UK
260e
Had similar problems - hope this helps.
I used a multimeter to measure the current drainage across the battery by disconnecting the positive lead, connected th meter to the battery & then the positive lead to the other end of the meter, thus completing the circuit.
I then removed the fuses one by one until the current drainage changed for the better.
In my case the problem was fuse 9.
I haven't found why this is the problem, but I haven't replaced the fuse as all it seems to do is keep the clock running when the ignition is off & works the courtesy lights whern the doors open, both of which I can live without.
Good luck !
I used a multimeter to measure the current drainage across the battery by disconnecting the positive lead, connected th meter to the battery & then the positive lead to the other end of the meter, thus completing the circuit.
I then removed the fuses one by one until the current drainage changed for the better.
In my case the problem was fuse 9.
I haven't found why this is the problem, but I haven't replaced the fuse as all it seems to do is keep the clock running when the ignition is off & works the courtesy lights whern the doors open, both of which I can live without.
Good luck !
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i had a problem similar to yours ... it turned out to be a piece in the alternator called the Voltage Regulator ... 2 magnetic strips that eventually fade away, and when this occurs, the battery is not resupplied properly and can drain your battery overnight.
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salehjm is this pieace something I can pull out myself with out having to do any mechanics I also notice that you said at the bottom if its programed you can hack it what does that mean that this piece is programed so it can work
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mmarks
I was not clear with your instructions i disconect the positive from the batterry then take the multimeter and connect the neg to the neg on batterry and the other end of the multimeter to the batterry positve or to the positive lead that comes from the car the cable i mean that would go to the positve on the battery
I was not clear with your instructions i disconect the positive from the batterry then take the multimeter and connect the neg to the neg on batterry and the other end of the multimeter to the batterry positve or to the positive lead that comes from the car the cable i mean that would go to the positve on the battery
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GUYS also I checked the fuse box with the car closed and a few fuses are with power and they are 4 in total
1.D= auxiliary fan
2.C= rear roof light trunk light rear door locking sys central locking sys door lights, aut. antenna, control unit seat adjustment memory
3. fuse #9 diagnostic term 6, hazard warning system, clock, front roof light, radio, vanity mirror light, relay comfort circuitry term 86
4. fues #10 heatable rear window
All this fuses seem to be supplied with power when the car is closed
Are they suppose to have power even if the car is in the off position closed with the ignition key in my pocket
I feel I may be getting closer to the issues at hand with your help guys thank you
1.D= auxiliary fan
2.C= rear roof light trunk light rear door locking sys central locking sys door lights, aut. antenna, control unit seat adjustment memory
3. fuse #9 diagnostic term 6, hazard warning system, clock, front roof light, radio, vanity mirror light, relay comfort circuitry term 86
4. fues #10 heatable rear window
All this fuses seem to be supplied with power when the car is closed
Are they suppose to have power even if the car is in the off position closed with the ignition key in my pocket
I feel I may be getting closer to the issues at hand with your help guys thank you
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i suggest that you take is to a mercedes specialist ... it is a very cheap job .... shouldnt be more than 100 total ... the part itself is like 20-30 and some labor. the other part, about the programmed part, i am a computer programmer and hack things =] that's all.... rest assured, i dont hack for fun. good luck.
