Battery drain problem

E

essdeeay

Guest
Hello, this is my first post here...

My father has a 2000 CL-500 4.2 V8, which has developed a problem where the battery drains flat if left for more than a few days.

He's had an electrician look at it and it's been narrowed down to fuse #61 (blue fuse, 15amp) for command centre (satnav/radio/cd changer etc.). There's about 0.5 amps of current drain on the battery when everything is turned off. When fuse #61 is pulled out, there is no current drain at all, but then you can't lock the car.

Any suggestions, or perhaps a wiring diagram which might help in a fix?

Many thanks,
Steve
 
OP
E

essdeeay

Guest
  • Thread Starter
  • Thread starter
  • #2
Correction - it's a 5.0 V8.
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
341
Age
87
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
OK if the comand is staying awake then something wrong on the CAN.

I am just finishing off a DIY on this and it will be ready in 2 days
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
341
Age
87
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Just to help out a little more on this the most likely failure will be the telephone amp in the armrest if a telephone is fitted to the car, one could just unplug it but the D2b ring will be open circuit, if the car has Bose then this continues after the phone amp. It will need a dummy D2b plug to complete the circuit to be sure.

All checks should be done on the CAN bus
 
OP
E

essdeeay

Guest
  • Thread Starter
  • Thread starter
  • #5
Thanks for the replies. Both me and dad are little more than incapable enthusiasts (yes, possibly an oxymoron), so please bear with us!

There wasn't to our knowledge ever any telephone fitted to the car.

Is there a wiring diagram that covers items connected through fuse #61, and failing that, is there anything we can start pulling out one-by-one until we find the source of the drain?

I note, the alarm-siren and a telephone amp (if fitted) have already been suggested, and we'll make sure we try those.

Thanks again,
Steve
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
341
Age
87
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Sadly this fault may not get solved with the pulling of fuses, the whole comand system is all part of the CAN systems and it could well be that the only way to tell what is causing the drain is to measure the voltages on the CAN bus.

Once you pull a fuse all components are isolated, and in a ring.

I can certainly guide you through the testing but you do need some idea of how electronics function, it could be the phone amp if fitted in the arm rest, it could be the comand head unit, the OCP, CD changer.

If you cannot get this deeply involved one can cheat and fit a relay to shut the whole comand down when the car is not running
 

You lost your key ? Or maybe you need a spare! Your vehicle imobilliser does not respond anymore? WE CAN FIX THEM ALL !! Mobile ! Save Time and Increase Profits With us !
Top Bottom