W220 battery drain

[richjohn]

Hi my S320 is having a problem where by the battery is slowly draining? (over night) i notice that a while after i lock it (5-10mins or more) the wing mirrors fold back open? i have also noticed that the RF key remote stopped working (and after a car battery re-charge started working again?) also the interior light does not always come on when i unlock it? also the wing mirror glass forgets it driver setting? it seems like it might be (i think) something to do with the overhead panel module? as all these items work through this module i think? not sure? Can anbody throw some light on my problem like a loose connector maybe? if so which and maybe where?
Thanks all Richard

 

[Dec]

Try testing your car alarm… http://www.mbclub.co.uk/forums/electronics/169666-w202-how-test-car-alarm.html

What year is the car?

Dec

 

[richjohn]

W220 battery issue

Hi thanks for reply, my car is an 04 reg and the alarm is working fine? Richard

 

[Dec]

Some of the symptoms you describe can be related to the alarm so always the first thing to test.
Ailing car battery perhaps?
Is the car used infrequently or perhaps been off the road for some time.
In the absence of any other advice you could have the car put on diagnostics to see what might be revealed.

Dec

 

[richjohn]

Hi, i have used xentry system and the faults just return with low battery mainly so i fitted new 900amp battery and reset the codes? Richard

 

[Diesel Benz]

Would an alarm issue make wing mirrors fold open at any time? Sounds to me like some bigger issue, SAM failed or something like that.

There are many typical quiescent current problems, memory seats, COMAND/NAVI processor, in addition to the alarm. If the drain is really high, it could be the electric heating element (this is a CDI).

Quiescent current measurements (follow WIS instructions) could reveal the issue but if the current is intermittent, it might be difficult to catch.

 

[Dec]

Most of those faults are related to locking and unlocking, as is the car alarm, while the alarm, when tested, might seen to work properly, it should not be trusted as it is now 11 years old… if it is the original siren… I would disconnect the alarm siren to see if any change in the faults.

Is the car used infrequently or perhaps been off the road for some time.

Dec

 

[richjohn]

I have fitted a second hand siren 12 months ago due to little recharable battery not holding charge (which caused the indicators to flash all the time) and it has been fine since then. I do use the car daily. i will disconect siren and like you say and see what happens? Also can you throw any light on what wis to follow or make a start with? i know this might be difficult but just by me asking a question any answers might start me thinking if you see what i mean? Help so far has been brilliant thanks again. Richard

 

[Dec]

The second hand siren is likely to be just as old as the car, unless you know otherwise.
Have the car unlocked when you disconnect the siren otherwise it will go off if the alarm is armed. Leave it disconnected for a few days. It might prove nothing but worth a try.
After you disconnect the alarm siren you might disconnect the car battery negative terminal for ½ an hour as well.

Sorry can’t help with wis.

Dec

 

[richjohn]

Ok cheers i will give it a go and let youm know. Richard

 

[Dec]

Just for educative purposes, something to do with folding mirrors may or may not be relevant to your mirror fold/not dipping in reverse fault.
Dec

https://www.youtube.com/watch?v=ElIIDz-vq4w

[YOUTUBE]ElIIDz-vq4w[/YOUTUBE]

 

[richjohn]

Hi, So far so good i have disconnected the alarm siren and this seems to have stopped the battery draining. only time will tell. Cheers

 

[Dec]

Did disconnected the alarm siren fix ALL the faults in post #1?

Dec

 

[richjohn]

Yes except for the mirror driver memory settings? Cheers

 

[Dec]

Dont know much about mirrors, is there supposed to be a setting for the drivers side?
I thought there is memory for passanger side only which is related to reversing?

Dec

 

[Diesel Benz]

Dont know much about mirrors, is there supposed to be a setting for the drivers side?
I thought there is memory for passanger side only which is related to reversing?

Dec

The reversing mode is different, if you have memory seats, also mirror positions are stored.