Battery Charging

[mercedestommy]

I have an early 'new shape' CL600 which, unfortunately, does not have a back-up battery. If you do not use the car for 5 or 6 weeks, the battery goes completely flat.

The handbook says 'disconnect battery before charging'.

Once the battery is charged up, would using a battery charger for an hour a day on 'trickle' (just to keep it charged up) with the battery still connected, do any harm?

 

[colechelle]

no not at all,but the battery shouldnt go flat that quick, how old is the car ????

 

[mercedestommy]

The car is a 2001 model but it is low mileage and the battery is 12 months old.

 

[colechelle]

then i suspect that a body control module is draining it!!

 

[television]

Cole the max that my rear battery will stay up is 2 weeks, the CL is not so different in the electronics.

A suitable clamp meter would give the answer,50 ma is the max draw

At 50ma, thats 2.5 amps per day 14 days =35 amps gone

 

[colechelle]

I know, but you know yours has a prob, it should last longer than that all beeing well!!!!

 

[television]

I know, but you know yours has a prob, it should last longer than that all beeing well!!!!

I have no problem on mine as its modified,, but a current check would tell all, even with a 25ma drain that is 35 amp in a month

Amweby on the other forum had a problem on his CL500 and that was the seat controller down and the best figure that MB could get it down to was the 50ma

 

[colechelle]

I have no problem on mine as its modified,, but a current check would tell all, even with a 25ma drain that is 35 amp in a month

Amweby on the other forum had a problem on his CL500 and that was the seat controller down and the best figure that MB could get it down to was the 50ma

Hence what im saying malc, something draining it!

 

[wireman]

Malc where on earth does a 0.050A drain times 24 hours yield 2.5AH?

I make it 1.2AH.

 

[television]

Malc where on earth does a 0.050A drain times 24 hours yield 2.5AH?

I make it 1.2AH.

Full marks for spotting the silly mistake.

Truthfully one of the AA cells in my head was low :sad:

Yes 100ma in 2 hours make you correct, and I then went wrong,:sad: I still do not think that they can go 6 weeks