eurdone

Hey folks, I have an '06 S55 AMG pulling about 2.5A when it should be sleeping. My mechanic narrowed it to the Audio Gateway. I'm destroying brand new (strong) batteries, beyond recharging, within weeks.

I've researched these forums extensively, and I'm hoping it might just be the nav disc. I read the next step is to disable the nav disc reader altogether. I've read others suggesting buying the T3 battery brain to force the AGW to sleep--I'd rather not go this route unless absolutely necessary. Sounds like it would just be an interim step while diagnosing anyway. And I really don't want to disable my entire audio system. Seems like replacing the AGW is complicated and involves reprogramming? Please tell me there could be a simple solution to this.

My mechanic noticed the optical cable is still awake when the car is off. Any suggestions would be most appreciated. A side note, not sure if this carries any relevance, but I did replace the COMAND screen unit a few months back because it had gone dead and would not power on.

Thanks,
John

pmercury

iTrader: (2)

You need Xentry DAS first to see if the new command has been paired correctly in Central Gateway and setting in Command are correct
that might just be the cause

Kebowers47

The Command unit is malfunctioning and keeping the Optical Fiber network "live" which is an extra parasitic drain. It is also "waking up" other components increasing the drain. I suggest some robust drain testing by pulling fuses one at a time (in logical order) while monitoring the battery drain. Since most everything is 'fused', this should absolutely locate the 'drain.'
Somewhere there is a relay (mechanical or solid-state) stuck 'ON.'

pmercury

iTrader: (2)

pulling fuses works only on some places as other concerned moduls will trigger errors for defects
pulling fuses is something that works on cars with little electronics
also, after each pull you would have to wait the car to go asleep, block door sensors, hood sensor ect

eurdone

Still at a total loss on this one... Any other ideas? I read a faulty fan can fry the AGW. Also some people have said water damage can be the issue, but I don't think the trunk has been exposed to water.

pmercury

iTrader: (2)

Get Xentry Diagnostics and SDconnect 4

Kebowers47

There are numerous electronic and electro-mechanical devices in this car and the best way to locate the fault is by using the Mercedes Diagnostic Software and a competent MBZ tech. Using the Dealer facilities (I include the competent techs as Dealer facilities)will likely be far lower cost and much, much faster.

pmercury

iTrader: (2)

or ask me