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Battery drain solution found

chappardababbar

E500E Enthusiast
Member
Okay after a whole year of trying almost everything to find out why my battery is flat within 2 hours of shutting down the car, and having to disconnect the battery all the time, I found the solution by accident.

I've taken the car to all manner of auto electricians/MB technicians who couldn't figure out what the problem was. Just today I asked my tech to replace my battery with a new MB one for no reason other than I wanted a battery that filled the battery space properly, and the problem was sorted. Just like that.

Everyone I went to said the old battery was fine, strong, holding charge well and definitely not the problem. This was clearly wrong and I think there may have been some kind of intermittent problem with it. Also, the car starts up more quickly and turns over more aggressively than ever before :D

Moral: If all else fails, buy a new battery.
 
Sometimes if you look at a battery, if you look at the sides of the casings you'll see that they are bowed out, when this happens you can get the plates touching each other and shorting internally. A good way to test this is (assuming you have a battery you can look at the electrolyte in by removing the caps) is get a multimeter, take off the caps, put the black leade on -ve and then dip the red probe in the electrolyte, each cell should contribute no less than 1.2v/cell on a fully charged battery, by the time you get the end last cell which is closest to the +ve terminal you should be at a about 12.6v (a fully charged battery is 12.6v not 12v as many people believe). Another test whist you are at it is pull the crank sensor lead of the EZL and crank the engine, look for bubbles appearing in each cell, any that do mean that cell is shot and the battery should be replaced.
 

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