E55 AMG Wagon Mystery Parasitic Battery Drain

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Silverarrows

Member
Joined
Aug 16, 2021
Messages
47
Location
Cheltenham, Gloucestershire
Car
E55K AMG Wagon 2003 (S211) Black, Daimler Double Six Coupe V12 '77, Volvo Amazon 121 Coupe '67.
Please can anybody help?

My 2003 E55 AMG S211 wagon has a mystery parasitic battery drain for years.

Other W211, S211 owners must have suffered frustrating and time consuming battery drains?

It draws key-off, and gone-to-sleep, 350mA on my meter when the specification is 40mA to 60mA maximum?

This drains battery over the weekend.
Sometimes battery will drain overnight, so draw may be intermittent and sometimes much higher?

Meter connected correctly in series with negative main battery cable in boot,
Brand new Yuasa 100 Ah battery.
Old Auxiliary battery under bonnet, measures 12.6v.

Pulled all fuses one by one, drivers side panel, under bonnet, rear left side panel, waited until modules went to sleep, still 350mA?
Suspected usual seat modules so disconnected power cables, no improvement to draw?
Suspected alarm siren, tested OK by locking car with open window and then inserting arm, siren goes off and lights flash but sounds very weak?
No aftermarket electrics,

I can only think of a couple of things left to try is:
Fuses by battery positive terminal and faulty alternator?

I have heard of CD players and Command units mysteriously drawing current overnight on W211's and S211's?

I think this is certainly a module staying awake?
Why is this not isolated when I remove a fuse?

Any help will be greatly appreciated.
 
Have you checked the Door control module inside the drivers door?
That was the culprit when I had a drain on my previous E55.
Have you checked the Overhead Control Panel for a drain? It's often overlooked.

Pull the fuse on the Comand overnight and see if that solves the problem.
It's Fuse F3 in the boot. 7.5amp.

If you want a copy of the W/S211 E55 fuses and relays, send me a PM when you have 60 posts with your email and I'll send you one.
 
If not Comand, then also disconnect the keyless module as I think they can also be problematic.

They are a pain to track down. 🤪 :wallbash:

…. I had one on my CL 500 at one stage. After much head scratching, hours of testing,…. Turned out to be my 9month old battery had an intermittent internal fault (lucky it never caught fire!) …… I’d kind of ignored it as it was ‘new’ ……a new Bosch and it was fixed 👍 :banana:
 
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Once had that in my 211. In my case it was the phone module staying on for some random reason. Once the faults were cleared it never did it again.
 
Car Wizard gives a basic check on this , he might show you a tip you might have missed. But it does sound like you have done most he shows here. Best of luck.

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as above

door modules, comand, keyless modules, audio gateway, all of these can drain, so fuses out for each one at a time to check.

good luck, this always take patience to solve.
 
Mines was the driver and passenger seat modules. I took out the fuses from the right side of the steering wheel area. think it was fuse 28 and 29 and Graham from PCS done the £2 fix where he cut the live feed off so it only works when ignition is on. So far so good.
 
If not Comand, then also disconnect the keyless module as I think they can also be problematic.

They are a pain to track down. 🤪 :wallbash:

…. I had one on my CL 500 at one stage. After much head scratching, hours of testing,…. Turned out to be my 9month old battery had an intermittent internal fault (lucky it never caught fire!) …… I’d kind of ignored it as it was ‘new’ ……a new Bosch and it was fixed 👍 :banana:
I will try another battery.
Thanks
 
Once had that in my 211. In my case it was the phone module staying on for some random reason. Once the faults were cleared it never did it again.
Phone module?
I will try to locate this and isolate it, thanks!
 
Phone module?
I will try to locate this and isolate it, thanks!
I can't recall quite how it was diagnosed but it was basically failing to shut down for some obscure reason. Once the fault codes were cleared and everything reset it never did it again.

My 211 threw quite a few intermittent electrical wobblies in the years I had it. Usually of no significance at all but occasionally inconvenient - like that one.

The 212 systems seem to have eradicated those tendencies. Probably due to more testing/more processing power/more memory/better code.
 
Thanks, I think I have the same issue of modules not shutting down, so cleared all error codes again with my iCarsoft MB V2.
Cannot clear hall sensor error with drivers seat back- forward motor, sometimes will not work when fully back?
I think the cabling is compromised?

Saturday, spent all day pulling every fuse individually from all three fuse boxes and checking for a change in the draw.

Some fuses when removed would wake up modules and increase draw to 5-8 Amps!
Checked with Sat/Nav DVD in and out, no difference.
Had to wait for them to go to sleep (3-8 mins) before checking draw on my meter - despite all this work could not get it below 0.16A which is much too high!

Success on Sunday
Parasitic draw down to 25-30mA today after removing alarm siren from car and waiting 30 minutes - despite it working but sounding funny and weak?.
This is perfect and where it should be.

Will see how things go.
Thinking of pulling the drivers seat out next weekend.
 
I had something similar on my r230, it was traced to the front SAM, which was being “beaconed“ and woken up repeatedly by the keyless module. Oddly enough, it didn’t have keyless go, so the fix was to cut the feed wire. Problem solved.
 
Front SAM, ...............interesting?

I do have Keyless go, Distronic, Dynamic, heated and cooled seats, active curve bi-xenons, and the myriad of options below on my Wagon!
In fact I think the only option I do not possess is rear child seats and auto tailgate?

This problem now seems more challenging then first thought.
Especially the old phone which I cut, the old Analog TV tuner cannot be used I think?

Code Description
197U OBSIDIAN BLACK
205B OWNERS MANUAL AND SERVICE RECORD - ENGLISH
213 SPEED-SENSITIVE POWER STEERING/VARIO STEERING
219 PROXIMITY-CONTROLLED CRUISE CONTROL
220 PARKTRONIC SYSTEM (PTS)
221B SIGN COOLANT/REFUELING - ENGLISH
231 GARAGE DOOR OPENER
241 FRONT SEAT LH ELECTRIC ADJUSTABLE WITH MEMORY
249 INSIDE AND OUTSIDE MIRROR AUTOMATIC DIMMING
250A LEATHER
250B MOBILO LIFE/EUROPE SERVICE PACKAGE
251A LEATHER - BLACK/ANTHRACITE
265 LINES-NO.PLATE DISCONTINUED
275 MEMORY PACKAGE (DRIVER SEAT, STRG. COL., MIRROR)
287 THROUGH-LOADING FEATURE
293 SIDEBAG IN REAR LEFT AND RIGHT
354 ANTENNA FOR TELEPHONE D/E-NET
382 PORTABLE CTEL
401 FRONT SEAT CLIMATE CONTROL
414 ELECTRIC TILT/SLIDE SUNROOF IN GLASS VERSION
423 5-SPEED AUTOMATIC TRANSMISSION
433 LEFT DRIVING DYNAMICS SEAT
434 RIGHT DRIVING DYNAMICS SEAT
461 INSTRUMENT WITH MILES IND. AND ENGLISH LEGEND
475 TIRE PRESSURE MONITOR (TPM) HIGH LINE/MID LINE
489 AIRMATIC DUAL CONTROL / AIR SUSPENSION SEMI-ACTIVE
500 OUTSIDE REAR VIEW MIRROR LH AND RH FOLDING
527 COMAND DVD APS WITH NAVIGATION
537L GREAT BRITAIN AND NORTHERN IRELAND
543 SUN VISOR WITH MAKE-UP MIRROR L. AND R., BE-
551 ANTI-THEFT/ANTI-BREAK-IN WARNING SYSTEM
573 CHILD SEAT MOUNTING, ISOFIX IN REAR
581 AUTOMATIC CLIMATE CONTROL
5XXL EUROPE
600 HEADLAMPS - CLEANING EQUIPMENT
616 BI-XENON HEADLICHT W.ACTVIE CURVELIGHT LEFT-DRIVE
668 PRODUCT PROT.F.TRANSPORT VEH. W/ TIE-DOWN HOOKS
673 HIGH-CAPACITY BATTERY
682 FIRE EXTINGUISHER
772 AMG STYLING PACKAGE-FRONT SPOILER, SIDE SKIRT
804 YEAR OF MODIFICATION
810 SOUND SYSTEM
819 CD CHANGER
860 TV-TUNER ANALOG
875 HEATED SCREEN WASH SYSTEM
882 INTERIOR SAFEGUARD
889 KEYLESS - GO
910 DYNAMO WITH HIGHER CAPACITY (FFO)
915 FUEL TANK WITH LARGER CAPACITY
926 EXHAUST GAS CLEANING WITH EURO 4 TECHNOLOGY
954 EQUIPMENT PACKAGE FOR AVANTGARDE VEHICLES
984 COC DOC., DELETION OF VEHICLE REGISTRATION DOC.
989 IDENTIFICATION LABEL UNDER WINDSHIELD
M001 ENGINES WITH SUPERCHARGER
M113 V8-GASOLINE ENGINE M113
M55 CAPACITY 5,5 LITRE
U15 2ND CARGO AREA W/ COMPART. UNDER MAIN FLOOR PANEL
U16 STOWAGE TANK BEHIND REAR SEAT BACKREST
 
Contant charging and re-charging because of my E55 parasitic drain has now killed my Yuasa battery.

Purchased new AGM battery but seems to intermittantly fully drain battery over the weekend - some weekends no drain - other weekends battery totally dead on Monday?

Watched 'Car Wizard 's' video again from Petrol Pete........ I now have invested in an 'AMP HOUND' from Cal-Van tools USA.

Checked all fuses with the 'Amp Hound', Drivers side panel , under bonnet and in rear left by tailgate - but no draw on any fuse?

Really puzzled, but determined to solve the issue.
 
If I read correctly.. you said removing the Alarm siren .. reduced your current draw considerably..to where it should be? the siren has a backup rechargeable battery, that will eventually fail and not charge, so will continue to draw on your battery. The batteries, inside when old , can leak onto the printed circuit board and send weird signals to the SAM modules. The fact the siren sounded weak should be a clue ( mine made no sound at all on my R230- ) when I replaced my alarm siren.. the intermittent keyless go has sorted itself.. now works every time.. battery still full after 2 weeks of non use.
My siren was about £90 from MB parts.
You can apparently replace the rechargeable batteries , but it was simple plug and play with a new one.
Hope this helps.

John
 
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Interesting..................disconnected and removed my alarm siren over a year ago, still have a draw, I dont really need an alarm siren, where is the backup battery, is it in the siren itself?

Should removal of the siren unit eliminate a possible amperage draw?

Thanks for your help!
 
Ah OK, the siren has a built in back up battery on mine.. not sure about yours.. but the Alarm system could be restless looking for the siren, or be in limbo.. and not powering down.

Trackers are sometimes fitted to cars and they have a simular situation.. with their backup battery trying to charge too.. they charge from the car too, and often their built in battery needs to charge but cannot .. and keeps trying.
 
Ah OK, the siren has a built in back up battery on mine.. not sure about yours.. but the Alarm system could be restless looking for the siren, or be in limbo.. and not powering down.

Trackers are sometimes fitted to cars and they have a simular situation.. with their backup battery trying to charge too.. they charge from the car too, and often their built in battery needs to charge but cannot .. and keeps trying.
Ok, thanks.
I will Investigate further.
 
The alarm siren on the E55 is the same internal battery which leaks, replace the siren as suggested and you should be OK,
 

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