SL/R230: Changing Trunk Battery Myself - Safe ??
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Joined: Nov 2004
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From: Seattle, WA
2003 SL500 Sports Package
Changing Trunk Battery Myself - Safe ??
This sounds dumb and I can easily do it. However I do not know how to perform any neccessary reset of the electrical computer in the car ?
I don't want to get stuck having to go into the dealer just because I did not know how to reset something.
However it seems like this should be safe. After all the battery can go dead on it's own.
Am I safe to just remove the trunk battery and replace it ?
I don't want to get stuck having to go into the dealer just because I did not know how to reset something.
However it seems like this should be safe. After all the battery can go dead on it's own.
Am I safe to just remove the trunk battery and replace it ?
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BMW F02 (750Li) F10 (550i)
This sounds dumb and I can easily do it. However I do not know how to perform any neccessary reset of the electrical computer in the car ?
I don't want to get stuck having to go into the dealer just because I did not know how to reset something.
However it seems like this should be safe. After all the battery can go dead on it's own.
Am I safe to just remove the trunk battery and replace it ?
I don't want to get stuck having to go into the dealer just because I did not know how to reset something.
However it seems like this should be safe. After all the battery can go dead on it's own.
Am I safe to just remove the trunk battery and replace it ?
Remove the + side cable than remove the - side cable. install the new battery by connecting the - side cable than the + side . after everything is done restart your car. you will have this following issues.
1st the windows won't go up when you shut the doors , so simply lower all the windows down then up 1,2, or 3 times to reset them all, eventually it will work.
2nd you should get some lights on the dash , you can reset it by turning the wheel all the way around to the right, then left 1 or 2 times (either way you want to star turning) and all your problems are solved .
Senior Member
Joined: Oct 2006
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From: Southcoast England
CL500 216
Excuse me saying this.
Always remove the neg first,,if a spanner touches any metal part of the car,,no sparks or damage.
To re set windows close them and hold the switch up for 10 sec in key 2. To re set the ESP lamp on dash,, turn the steering wheel 3 times from lock to lock
Always remove the neg first,,if a spanner touches any metal part of the car,,no sparks or damage.
To re set windows close them and hold the switch up for 10 sec in key 2. To re set the ESP lamp on dash,, turn the steering wheel 3 times from lock to lock
MBWorld Fanatic!
Joined: Oct 2008
Posts: 1,746
Likes: 1
BMW F02 (750Li) F10 (550i)
Excuse me saying this.
Always remove the neg first,,if a spanner touches any metal part of the car,,no sparks or damage.
To re set windows close them and hold the switch up for 10 sec in key 2. To re set the ESP lamp on dash,, turn the steering wheel 3 times from lock to lock
Always remove the neg first,,if a spanner touches any metal part of the car,,no sparks or damage.
To re set windows close them and hold the switch up for 10 sec in key 2. To re set the ESP lamp on dash,, turn the steering wheel 3 times from lock to lock
Last edited by m4xm1l10n; Dec 5, 2008 at 10:17 PM.
Senior Member
Joined: Oct 2006
Posts: 379
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From: Southcoast England
CL500 216
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Joined: Aug 2007
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2003 SL500
Sorry but....
I spent years working on Healeys, MG'S Austins, Hillmans, Sunbeams, Mini's, Humbers on up to Rolls Royce and Jaguar. I can't tell you the mess it made when some yahoo American mechanic improperly put a battery in a car that was supposed to be POSITIVE EARTH. IE: putting it so that the negative terminal was the chassis instead of the positive one.
You ended up with a car with a burned out radio, a generator that couldn't charge and a regulator that had the polarity reversed.
The "cutout" you describe must have been missing from all the cars I worked on, more to the point: There wasn't one!
If what you say was true everyone would have done it. Go to any car show today, find a car from 'Ol Blighty and see how many are STILL positive earth they way they were intended. Yes it's a pain but it worked.
Cheers from across the pond,
J T
Senior Member
Joined: Oct 2006
Posts: 379
Likes: 3
From: Southcoast England
CL500 216
I don't know what shops you worked in on Brit cars or what your credentials are.
I spent years working on Healeys, MG'S Austins, Hillmans, Sunbeams, Mini's, Humbers on up to Rolls Royce and Jaguar. I can't tell you the mess it made when some yahoo American mechanic improperly put a battery in a car that was supposed to be POSITIVE EARTH. IE: putting it so that the negative terminal was the chassis instead of the positive one.
You ended up with a car with a burned out radio, a generator that couldn't charge and a regulator that had the polarity reversed.
The "cutout" you describe must have been missing from all the cars I worked on, more to the point: There wasn't one!
If what you say was true everyone would have done it. Go to any car show today, find a car from 'Ol Blighty and see how many are STILL positive earth they way they were intended. Yes it's a pain but it worked.
Cheers from across the pond,
J T
I spent years working on Healeys, MG'S Austins, Hillmans, Sunbeams, Mini's, Humbers on up to Rolls Royce and Jaguar. I can't tell you the mess it made when some yahoo American mechanic improperly put a battery in a car that was supposed to be POSITIVE EARTH. IE: putting it so that the negative terminal was the chassis instead of the positive one.
You ended up with a car with a burned out radio, a generator that couldn't charge and a regulator that had the polarity reversed.
The "cutout" you describe must have been missing from all the cars I worked on, more to the point: There wasn't one!
If what you say was true everyone would have done it. Go to any car show today, find a car from 'Ol Blighty and see how many are STILL positive earth they way they were intended. Yes it's a pain but it worked.
Cheers from across the pond,
J T
If you were going to change the polarity of a car from positive to negative earth, one would do that to help stop rust or just to fit a negative earth radio, as the positive earth versions all went off the market during the 60's
If you fitted a battery the wrong way around in a car with a dynamo and cut out box nothing would happen other than. it would not charge. the reason for this is that the magnetic core of the cutout would be wrongly polarized, and it would not close.,,, I said in my post that if you hold the cutout closed,that will reverse the magnetic polarity, and it would then charge. there is nothing on a car that used a dynamo that could be damaged other than the radio.
I must have done some 200-300 cars when I had my car radio shop in Watford, Herts during the mid 50's to 1970
If you look at any wiring diagram, one must have a cutout, for a dynamo will run like an electric motor if left coupled up to the battery as it. So every car with a dynamo has a cutout, there were 3 main variants of cut outs, from a basic cut out to start with, next came the voltage controlled and the last were both current and voltage controlled, the on thing in common was that they all incorporated a cut out for the reasons above
Junior Member
Joined: Aug 2007
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2003 SL500
Hmmm now you make me wonder...
Well said I think we might even be on the same page but are differing in terminology.
When you say "cutout" where is it or was it it located?
The only thing that comes to my mind is the battery disconnect in a Healey 3000's trunk or the pushbutton for the solenoid on a lot of the older cars. None of this counts as a cutout... so please clarify if you would be so kind.
Regards,
J Tinsby
Senior Member
Joined: Oct 2006
Posts: 379
Likes: 3
From: Southcoast England
CL500 216
Hello again,, it could have been called the voltage control box, it was always mounted on the firewall as near to the dynamo as possible to avoid any influence of the cars electrics. The cut outs job was to disconnect the dynamo at idle.
