Bentley Publishers - Technical Discussions : BATTERY KEEPS DYING OVERNIGHT ...

ositopadi

Posts: 10
Registered: 09/17/07

BATTERY KEEPS DYING OVERNIGHT
Posted: Sep 20, 2007 5:48 AM

C Class 180 Elegance.
It worsened over the past five months and I have to disconnect the battery each night.

Question: The electric roof and windows keep functioning after engine switched off. WOULD THIS BE THE PROBLEM???

I wish someone would shed some light on this please as garages estimate above $ 600.00 to isolate the problem.

Thanks Guys.

alfhoc

Posts: 34
Registered: 04/23/07

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Sep 20, 2007 2:35 PM

in response to: ositopadi

Reply

Please do the following: switch off the ignition and withdraw the key! Work in a will light area. Disconnect the pos + (red) terminal of the battery, then connect a digital multimeter (or and dc amp meter) on the AMPS scale between the battery and the terminal you have taken off. this will allow you to read the current draw off the battery.Take the reading.(i.e.3 amps) now open the fuse box in the engine compartment.PULL ONE FUSE AT A TIME WHILE TAKING A READINGS OF THE METER. remember to replace every fuse pulled, BACK into its original position IF THE CURRENT DROPS (i.e. 1.5 amps) you will know that the circuit is drawing current. Now look on the inside cover of the fuse box and find the fuse location and number (i.e. fuse 14 may be for the brake lights or turn signal)Your owners manual will also give you this information. You will then have located the circuit that is drawing your battery down when standing.you can then take the necessary action. Remove the multimeter,connect the battery terminal and set the radio code. I hope I have assisted you. Cheers

autobahn

Posts: 515
Registered: 08/17/05

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Sep 20, 2007 5:12 PM

in response to: alfhoc

Reply

Be very careful putting any analog multimeter or DVM etc directly into the positive or negative cable, since the typical current range is 10A. You might damage your multimeter beyond repair. In some cars electrical systems switch off in stages and the initial current draw might exceed 10A.

Shunting or a amp meter with pliers as current "sensor" would be my choice.

ositopadi

Posts: 10
Registered: 09/17/07

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Sep 22, 2007 2:38 AM

in response to: ositopadi

Reply

Thank you very much guys, I am to get that multimeter now and let you know the results. U might have saved me a bob.
Cheers guys.

ositopadi

Posts: 10
Registered: 09/17/07

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Sep 22, 2007 8:16 AM

in response to: ositopadi

Reply

Thank again mates...It was the 15A fuse!!! Central locking system and infrared Remote Control.

I shall now look into more detail.

All the best to all the forum.

alfhoc

Posts: 34
Registered: 04/23/07

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Dec 12, 2007 4:01 PM

in response to: ositopadi

Reply

HI, PLEASE GIVE US SOME FEEDBACK AS TO WHAT THE PROBLEM WAS,THAT'S TO SAY IF YOU LOCATED THE PROBLEM,CHEERS. ALF

Bimmerman4Ever

Posts: 15
Registered: 06/20/09

Re: BATTERY KEEPS DYING OVERNIGHT
Posted: Oct 13, 2009 1:55 PM

in response to: ositopadi

Reply

bump