W211 battery error message

[migabc]

Hi everybody,

Recently these 2 malfunctions have been showing up on the MFD in my W211:

RED - “BATTERY/ALTERNATOR – VISIT WORKSHOP"
and simultaneously
WHITE - "ELECTRICAL CONSUMER SWITCHED OFF"

I read somewhere that these 2 messages together usually mean that either one of these 4 situations occurred:
· battery control unit (N82) is defective
· the alternator (G2) is defective
· the additional battery relay (K57/2) is defective
· additional battery (G1/7) are defective.

In my case I think it’s the last one, because if I drive long enough the battery gets charged and the error messages disappear. If I leave the car parked for over 24 hours these messages reappear the next time I start the car. Btw, the car always starts up fine (almost immediately)

Am I correct to assume that the aux battery (the small one under the hood) is going bad?

Does anybody know the part number for this battery?

Is there a Varta or Bosch equivalent? Or am I stuck with the dealer?

Thanks,
Miguel

 

[DieselE]

I don't claim to be an expert but here's a couple of thoughts.

The Battery/Alternator alarm is probably being triggered by low battery voltage and the car is switching off non-essential circuits to maintain a starting ability. Driving the car until the alarms cancel does not mean you've charged the battery. It just means you've got the voltage up above that at which the alarms are reset.

Before you start changing anything I'd suggest you fully charge the main battery. The ideal way requires access to a spare 12V battery and a mains driven trickle charger.

1. Using jump leads, connect spare battery to main battery (in the boot) leads. This ensures that when you disconnet the main battery you do not lose any of the car's electrical parameters.

2. Disconnect main battery from leads (it's probably easier to then remove the main battery from the car).

3. Charge main battery on trickle charger for 24 hours.

3. Refit main battery in car, reconnect leads and finally disconnect spare battery.

With a bit of luck that will solve your problem.

 

[richard]

Consumers switched off message relates to the big battery being low - the small battery is used for starting and critical systems, the big for consumers (such as heated seats) and if its low things get progressively switched off (heated seats first, parktronic, etc)

How old is the car ? The original W211 & R230 batteries were a bit too small, MB UK quietly replaced them with larger ones when the cars were services. I don't know whether that happened everywhere or just to help a bit in countries with cold winters

Cheers

R

 

[Brian WH]

When I had a W211 there was a recall for this problem. Try your dealer to see if your vehicle qualifies.

 

[migabc]

Consumers switched off message relates to the big battery being low - the small battery is used for starting and critical systems, the big for consumers (such as heated seats) and if its low things get progressively switched off (heated seats first, parktronic, etc)

How old is the car ? The original W211 & R230 batteries were a bit too small, MB UK quietly replaced them with larger ones when the cars were services. I don't know whether that happened everywhere or just to help a bit in countries with cold winters

Cheers

R

It's a 2003 E220 CDI.
How can I tell if by battery is the correct one or not?
Do you know the part numbers for both batteries?

I find it hard to believe that the small battery under the hood is used for starting the engine. Starting a diesel engine usually requires a high capacity battery (that's why diesel engine batteries are bigger than gasoline engine batteries). Are you sure it's not the large battery in the trunk that is used for the starter?

I only get the battery alarm on the display when I leave the car parked for over a day. About a month ago when I left the car parked for a whole week the doors wouldn't even open with the key fob. I had to use the metalic key on the driver's door to get into the car – I though I wouldn't be able to start the engine because the interior lights were all off but when I turned the key in the ignition the car started up immediately (as it always did) but the battery alarm message was there (VISIT WORKSHOP + ELECTRICAL CONSUMER SWITCHED OFF) and the interior lights, parktronic, etc were all disabled. I then gave it some revs for a couple of minutes and when the interior lights, etc came back on I turned off the car. Then I tried the doors again and they were OK. I started the engine again and the battery alarm was gone (No malfunctions).

Are these the symptoms of a bad aux battery?
Has anybody experienced this?

Thanks,
Miguel

 

[Flash]

When I had a W211 there was a recall for this problem. Try your dealer to see if your vehicle qualifies.

There was a mass recall for W211s for this very issue but only affected cras from a certain build date/chassis numbers which I cannot remember.

 

[masqueraid]

MB Recall 31-3-2005: On E-Class and CLS-Class models made from January 2002 to January 2005, new battery control unit software should be installed to enhance the on-board power supply.

If you are only making short journeys (less than 10-15 miles at a time) there is little opportunity for the battery charging to be effective.
My home - work journey is <15miles and if I leave the car without a long drive I'll get the occasional battery warning. Checked with Star and is holding charge fine.

I use it as an excuse to do some long distance motoring

 

[DieselE]

I find it hard to believe that the small battery under the hood is used for starting the engine. Starting a diesel engine usually requires a high capacity battery (that's why diesel engine batteries are bigger than gasoline engine batteries). Are you sure it's not the large battery in the trunk that is used for the starter?
Miguel[/COLOR]

You're right. It's the battery in the boot that handles the starting load. The one under the bonnet (hood) is for the auxiliaries.

 

[migabc]

MB Recall 31-3-2005: On E-Class and CLS-Class models made from January 2002 to January 2005, new battery control unit software should be installed to enhance the on-board power supply.

If you are only making short journeys (less than 10-15 miles at a time) there is little opportunity for the battery charging to be effective.
My home - work journey is <15miles and if I leave the car without a long drive I'll get the occasional battery warning. Checked with Star and is holding charge fine.

I use it as an excuse to do some long distance motoring

I believe my car has all the recalls done already. The MB dealer usually takes care of that when the car goes in for servicing.

My daily journeys are around 25km (15 miles). On weekends I tend to do a lot more than that but I can still end up getting the battery alarm in the next day.

Should I try a full charge on the aux battery?
Is it safe to trickle charge the aux battery (under hood) without disconnecting it or should I disconnect it? If I do disconnect it will I loose some memory settings (or will the main battery supply those settings)?

Thanks,
Miguel

 

[glojo]

Hi Miguel,
We have suffered twice with this message. Our car very rarely does long journeys, but usually has no problems even though it sometimes remains in our garage for a week or two without being used

The first time they carriedout the modification that hasbeen posted AND just like has been mentioned they also put in a bigger battery. TWO years later we got the same message. This time it was traced to seepage. There is a defective module that is evidently prone to this and the car was leaking 0.6 of an amp thingie?? I am NO electronic geru, but this has been discussed on a different thread.

The car needs to charge the batteries, but if your driving habits have not changed and the batteries were okay, then I would suggest there is a reason for the battery going flat?

Good luck getting your problem resolved
John

 

[BTB 500]

After 4 years it may just be that the battery is on the way out. They start to suffer permanent damage below 12.4V (75% charge), so if the type of journey or some other problem/issue prevents the battery from being fully recharged after each start (or drains charge while it's standing) it will 'age' more rapidly.

 

[migabc]

After 4 years it may just be that the battery is on the way out. They start to suffer permanent damage below 12.4V (75% charge), so if the type of journey or some other problem/issue prevents the battery from being fully recharged after each start (or drains charge while it's standing) it will 'age' more rapidly.

Yeap! That's what I'm guessing as well.
My 4 year old battery is probably reaching it's end of life.

Should I replace both batteries or just the bad one (the aux under the hood)? Since the car has no problem starting I guess the main battery is still good.

Thanks,
Miguel

 

[Brian WH]

Yeap! That's what I'm guessing as well.
My 4 year old battery is probably reaching it's end of life.

Should I replace both batteries or just the bad one (the aux under the hood)? Since the car has no problem starting I guess the main battery is still good.

Thanks,
Miguel

Get them checked out properly first, you do not want to waste your money unnecessarily.

You will need to reset certain things after a new battery, so really needs specialist attention by a dealer.

 

[DansSlk]

Get them checked out properly first, you do not want to waste your money unnecessarily.

You will need to reset certain things after a new battery, so really needs specialist attention by a dealer.

While i agree that its best to get them checked before anybody goes forking out cash for one maybe even 2 batteries i think recommending a dealer do it is slightly too much you certainly don't need a dealership to check the condition on them and to replace them well to me that sounds like throwing money away.

migabc, if you do decide to replace the battery/batteries and want to do it yourself to save some cash you should find the info in the manual as to what needs to be reset if not drop me a PM i have the info here its just pressing and holding buttons.

 

[migabc]

While i agree that its best to get them checked before anybody goes forking out cash for one maybe even 2 batteries i think recommending a dealer do it is slightly too much you certainly don't need a dealership to check the condition on them and to replace them well to me that sounds like throwing money away.

migabc, if you do decide to replace the battery/batteries and want to do it yourself to save some cash you should find the info in the manual as to what needs to be reset if not drop me a PM i have the info here its just pressing and holding buttons.

Yes, I plan on doing it myself.
Thanks,
Miguel

 

[saorbust]

I'd suggest you look at the dealer option - they may replace the battery free of charge. Certainly thats whats happened to me - even on a car outside of the 3 year warranty.

They also use Star to update the BCS module software - which you won't be able to do no matter how many buttons you push. Don't forget to reset the ABS system by turning the wheel all the way from left to right and back again.

J.

 

[DansSlk]

I'd suggest you look at the dealer option - they may replace the battery free of charge. Certainly thats whats happened to me - even on a car outside of the 3 year warranty.

They also use Star to update the BCS module software - which you won't be able to do no matter how many buttons you push. Don't forget to reset the ABS system by turning the wheel all the way from left to right and back again.

J.

I think he would be lucky if they did that to be honest with you and he has said his car has already had the recall done to it so there is no need to play with the control module at all just a simple swap will do the trick.

Fair enough when the cars where arriving without the recall i was using the SDS as a matter of habit to ensure it was all OK but now it just add's time to a very simple job.

 

[markmulcahy]

While i agree that its best to get them checked before anybody goes forking out cash for one maybe even 2 batteries i think recommending a dealer do it is slightly too much you certainly don't need a dealership to check the condition on them and to replace them well to me that sounds like throwing money away.

migabc, if you do decide to replace the battery/batteries and want to do it yourself to save some cash you should find the info in the manual as to what needs to be reset if not drop me a PM i have the info here its just pressing and holding buttons.

Would you mind sending me the procedure please.....Mark Mulcahy

 

[Andy Stanton]

I had battery issues over the recent cold and snowy spell with my 2004 E220Cdi. Although not the same message it did state 'convenience features disabled to protect battery' on a daily basis. No heated seats for e.g. After a mile or so this resolved itself.

The main dealer had a look, updated the BCU (Battery Control Unit??) and gave the battery a boost - all under Service Plus.

Been fine ever since but it's also not been that cold to test it.

Interestingly one of my complaints was also that the heated seats too an age (two cycles) to get warm. This is now fixed too. Not sure if that's part of the battery boost or not.

 

[MB-KingOfCars]

Battery Control Module reset

While i agree that its best to get them checked before anybody goes forking out cash for one maybe even 2 batteries i think recommending a dealer do it is slightly too much you certainly don't need a dealership to check the condition on them and to replace them well to me that sounds like throwing money away.

migabc, if you do decide to replace the battery/batteries and want to do it yourself to save some cash you should find the info in the manual as to what needs to be reset if not drop me a PM i have the info here its just pressing and holding buttons.

Dan,
I'm going to be replacing the Battery Control Module in my car (2004 Mercedes E320 4matic), and I'm assuming that the electronics in my car will have to be reset, since this unit is connected directly to the rear battery. This is what I've found in the Owner's Manual:

"The following procedures must be carried out following any interruption of battery power (e.g. due to reconnection):
- Set the clock (page 143, See COMAND operator's manual)
- Resynchronize the side windows (page 200)
- Resynchronize the sliding/pop-up roof (page 204) or the panorama sliding/pop-up roof (page 209)"

saorbust also added "Don't forget to reset the ABS system by turning the wheel all the way from left to right and back again"

Is there any more to it?

Thanks in advance.