C270 CDI 4amp Battery drain

[142 TPL]

I have an intermitant battery drain that I am tring to track down. Car parked locked with bonnet up it rests at 0.02amps but sometimes it will show 0.02 amps then go up to 4.00 amps without touching any thing. So I start to pull fuses but then on its own it drops back to the 0.02amps it's driving me mad. It's completely drained the battery three times in the last year. I don't have full electric seats, does anyone know what draws 4 amps

 

[jaymanek]

Its a common issue on the W203... Could be one of the door control modules.

This is what you want

Car Fuse Current Battery Amp Meter Leakage Detector | eBay

 

[142 TPL]

Yep got one of them, the trouble is that the drain is so intermittent it's hard to track it down. I have a star and there are no codes

 

[stu]

Similar car (CLK270) , same problem. It takes about a week to go flat so it's only an issue when we fly away for holidays at which point I disconnect the battery. I'd love to find out what it is, all I know so far is it is not the tracker as I had that replaced on the assumption it wa.

 

[142 TPL]

I have just left mine for 2 weeks with no problem yet tomorrow it could be flat. I would rather it go flat all the time at least then I could trace the fault. My thoughts are
Heater booster
Overhead control module
Command
Alternator diode
I suppose I could see what each one drains and see if one is near the 4 amps

 

[stu]

I got to know quite a few Assist mechanics with this problem. One suggested it might be the electric seats which are always alive in a CLK in case you flip the seat forward so it can lower the headrest. Does your have electrically powered seats? (although the symptoms are diffeent. Mine is always flat after 2 weeks)