SL55/63/65/R230 AMG: New convenience battery lasts about 4 days
Thread Starter
Senior Member
Joined: Feb 2016
Posts: 328
Likes: 22
2004 SL55 AMG
New convenience battery lasts about 4 days
When my 2004 SL55 is not driven for about 4 days the brand new MB $275 convenience battery gives me a warning until I drive about 5-10 minutes...I'd like first hand experience on how long your's lasts.
I will use a battery tender but 4 days???
I will use a battery tender but 4 days???
Thread Starter
Senior Member
Joined: Feb 2016
Posts: 328
Likes: 22
2004 SL55 AMG
I'm pretty handy with a multi-meter...how do I use it to determine the "at rest" battery drain?
What is "normal/expected" at-rest amp draw?
Senior Member
Joined: Oct 2004
Posts: 471
Likes: 33
From: Germany
SL65 R230
Hi,
maybe the new Battery from MB was long in the store and was not fully charged?
AGM-Battery is fully charged at 12,6 - 12,8 V.
When you measure 12,0V or less I would not wait too long to recharge or to drive - not to damage the battery. After the winter my battery in the trunk had lets say 9 V, but I had luck - my old charger had resurrected it well and everything seems to be normal now.
Good luck!
maybe the new Battery from MB was long in the store and was not fully charged?
AGM-Battery is fully charged at 12,6 - 12,8 V.
When you measure 12,0V or less I would not wait too long to recharge or to drive - not to damage the battery. After the winter my battery in the trunk had lets say 9 V, but I had luck - my old charger had resurrected it well and everything seems to be normal now.
Good luck!
Thread Starter
Senior Member
Joined: Feb 2016
Posts: 328
Likes: 22
2004 SL55 AMG
Thanks all...I have determined how to check my amp draw (put multi-meter in series with disconnected negative terminal and read amp draw).
Questions:
1) Does trunk open (light on?) while I am doing this invalidate the reading?
2) Does disconnecting this battery wipe out any memory items (clocks, radio pre-sets, radio security, etc...) that will make it more difficult than it seems?
Questions:
1) Does trunk open (light on?) while I am doing this invalidate the reading?
2) Does disconnecting this battery wipe out any memory items (clocks, radio pre-sets, radio security, etc...) that will make it more difficult than it seems?
