W221 Comand warning.

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Diesel Benz
I do apologise, I completely forgot the Vin number.
The VIN is: WDD2210222A083940
 
I have no idea if Halfords will fit the rear battery for you,I suppose they might I would have thought £20 would do it,the back board of the rear seats has to be removed it will just pull out but is easier if say the left hand soft boot cover is removed first thats a couple of torx screws and ease out the left bootlight and disconnect the the connection to it,with the back board out the battery is at bottom right and once the strap holding it in place and the power leads are off ,it just slides out into the boot,very easy to change
 
zipdip
I went to Halfords and they told me that they do not stock or fit auxillary batteries.

My indy mechanic is going to do an oil/filter change in a couple of weeks before he get's it MOT'd. If I can find the correct reference number for the auxillary battery he can source/fit a replacement.
I have found that the only problems I am having because my aux is US, is the radio will not remain on with the engine switched off, and the windows go up slowly with the engine off, so the battery problem is not a major problem. (Probably why I am dragging my feet with it :))
Once again thanks to members on the board for being patient.
 
Thats right it is not a massive problem,the first thing you notice is the radio,but as it gets worse it will throw up all sorts of faults,the battery is just a large battery I am surprised Halfords do not have them,but as I said before make sure you have the right one fitted,because people put cheaper right size batteries in.
 
Diesel Benz
I do apologise, I completely forgot the Vin number.
The VIN is: WDD2210222A083940

This one has the 60 Ah battery from the factory, part number A0055411301.
 
Thank you very much for taking time out to help me Diesel Benz.

ps: I googled the part number and the batteries shown were all listed Starter Battery, now I am a little confused, (not hard)
A0055411301 is listed as the Starter Battery, am I correct in saying that on my 2006 W221 this is the battery under the bonnet, and the auxilliary battery is in the boot behind the rear seats?
 
Thank you very much for taking time out to help me Diesel Benz.

ps: I googled the part number and the batteries shown were all listed Starter Battery, now I am a little confused, (not hard)
A0055411301 is listed as the Starter Battery, am I correct in saying that on my 2006 W221 this is the battery under the bonnet, and the auxilliary battery is in the boot behind the rear seats?

Should have looked at both batteries. For this car the starter battery under the bonnet is the same part as the other one in the boot.
 
Diesel Benz, Unfortunately I am in my 8th Decade so not really able to crawl in the boot, remove the lining and check the battery.
I have had an in depth look in my W221 operators guide but I couldn't find any reference numbers for batteries so that is why I have sought help from the forum.

So, for final time then, both batteries are the same size/spec (A0055411301) and have the same type of terminal?

Hopefully all of your hard earned efforts may help other BM's in the future.
 
Diesel Benz, Unfortunately I am in my 8th Decade so not really able to crawl in the boot, remove the lining and check the battery.
I have had an in depth look in my W221 operators guide but I couldn't find any reference numbers for batteries so that is why I have sought help from the forum.

So, for final time then, both batteries are the same size/spec (A0055411301) and have the same type of terminal?

Hopefully all of your hard earned efforts may help other BM's in the future.

You are not that much more experienced than myself. ;)

I still had the EPC page open and it confirms that for this car the two batteries are the same (same part number, meaning the same terminal type too). I have made mistakes many times when reading parts information and I always promote forum members to check themselves if possible. If not possible, hopefully someone else here confirms. I wouldn't like you to lose the money because of my mistake(s).

Just checked the battery from EPC for my ex 221.122 from 2006, it had the same starter battery but a 95 Ah battery at the trunk (with option code 673, probably for colder countries).

The trunk battery can be reached without tools. The panel behind the rear seat at the trunk side comes off if grabbed from the top at one side. A bit of gymnastics to reach the panel. Removing the battery obviously needs tools.
 
The batteries are not the same size the one behind the rear seats is half as big again as the starter battery,I would suggest you get a more agile person to take off the back of the rear seats and then you will be able to see it,and then order a new one.
 
Thanks both, my Indy mechanic is having the car for a day next week for MOT, Oil /Filter change etc so I will get him to remove the panel, note which battery and then we can source one and fit it later.
I will keep the board informed as it will help someone in the future.
 
The batteries are not the same size the one behind the rear seats is half as big again as the starter battery,I would suggest you get a more agile person to take off the back of the rear seats and then you will be able to see it,and then order a new one.

You may be right, if the rear battery has been changed since the car left the factory. Here the EPC "shopping list" covering both batteries as they were from the factory for this car:
 

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The batteries are not the same size the one behind the rear seats is half as big again as the starter battery,I would suggest you get a more agile person to take off the back of the rear seats and then you will be able to see it,and then order a new one.

Forgot to say that it might be a good idea to install a bigger battery irrespectively if the original one is 60 Ah.
 
Hello BM's, I know that you are missing my updates. :)
So this morning I went to look at an E Class to see if I would be comfortable in one, but the E class had a footbrake pedal in the footwell and with my huge feet I just wasn't comfortable buying an E Class.
There was a main dealer close by so I went to ask how much the cost would be to fit a new auxillary battery to my W221, well after a lot of twoing and froing (nobody looked at the car), MB said according to all their IT systems my car only had one battery. This starter battery works brilliantly.
The impression I got from the MB parts guy was that as my W221 did not have many extras, then it was OK with just the starter battery, so after all this, my car doesn't appear to have a second battery.
Thanks for all your inputs.
 
Hello BM's, I know that you are missing my updates. :)
So this morning I went to look at an E Class to see if I would be comfortable in one, but the E class had a footbrake pedal in the footwell and with my huge feet I just wasn't comfortable buying an E Class.
There was a main dealer close by so I went to ask how much the cost would be to fit a new auxillary battery to my W221, well after a lot of twoing and froing (nobody looked at the car), MB said according to all their IT systems my car only had one battery. This starter battery works brilliantly.
The impression I got from the MB parts guy was that as my W221 did not have many extras, then it was OK with just the starter battery, so after all this, my car doesn't appear to have a second battery.
Thanks for all your inputs.

Please don't leave the topic yet. Attached a print from EPC with the VIN you provided earlier in the thread (didn't consider it necessary to read this from Parts Info, the battery has not disappeared since the car left the factory). I'd like to have this double-checked by some other forum member who has a bit of time and access to EPC or Parts Info.

Once checked, I'd like you to get in the trunk, pull off the rear trunk panel. Pull it from the top left or right side, the side panel gives room for your hand.

I've had an almost identical 221, 10 days difference in build date, even the same colour :), just the steering wheel differently placed etc.

I wonder if the parts guys looked at the parts without the vehicle VIN and concluded that the car does not have the bigger 70 or 95 Ah rear battery because those are only installed to cars that have certain accessories. The car would not have a big rear battery but it would still have the 60 Ah battery.

I've made mistakes many times when reading parts data and wouldn't be too upset if I made a mistake here but if it was a parts guy at an MB main dealer making this mistake, I'd approach his boss...
 

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DieselBenz Thank you very much for staying involved on this never ending thread. :)
I was convinced the auxillary battery was in the boot behind the rear seats, and I told my old school car mechanic this.
Whilst the car was having that new strut fitted he told me that he had removed the panel behind the rear seats and he felt there was a tray of some sort but no battery, he later looked at the side of the dashboard by the passenger front seat but found nothing.

It may not mean anything, but the Earth lead in the boot works, because I have to remove it when the clocks are altered to adjust my analogue clock, when I screw it back on I have had the very rare spark from it.

The impression I got from the parts guy was that there was more than himself trying to come up with an answer to my query.

In 3 weeks time I will be leaving the car at the train station for 5 days and it will be interesting to see if my remote unlocks the doors this time now that I have changed the batteries in the keyfob.

I still have plan Z up my sleeve, after looking at the E Class yesterday I am pretty sure that I will not be changing cars in the near future.
My final call yesterday was at a MB Indy company who I wanted to speak to about my steering wheel going in and out but not up and down. They told me they had done one before and a kit with Labour would be just under £400 so I am going to go along with that. Whilst the car is with them I will tell them to see if the car has the elusive 2nd battery. :)
 
OK, very interesting, would be unlikely that a mechanic working on the car would have missed the battery. EPC too has some errors every now and then but not often.

The facelift 221 (most of them) do not have any battery at the trunk but I doubt anyone would have reworked the car that way.

Would be nice to know if anyone is aware of any reasons for a pre-facelift without the rear battery.
 
Just a small update for members who have been following this thread.
Last week I left my W221 at the railway station on Tuesday morning and did not collect it until Saturday evening.
The remote key worked fine this time after I had changed the key batteries, also the car burst into life as good as gold on startup.
So I feel a lot happier now that I know it was the key batteries which caused the problem last trip.
My car is going to the Indy on Wednesday for the steering wheel motor repair and I may mention my pre facelift not appearing to have an auxilliary battery and if they have time just have a quick look around the car.
 
Hopefully the problem has cleared itself. I just doubt the battery in the smart key would have any influence on the COMAND switching off soon after ignition turned off (I think this was the main issue, the car has started fine all the time?).

This car does not have Keyless Go, the key battery is only needed to open and close door locks remotely. The key works fine when inserted to the ignition slot even if it had no battery at all.

We'll stay tuned to the channel for further news (hopefully none and the car works fine).
 
Cheers DB, yes no dash warnings about the auxilliary battery, no starting problems with the car from the starter battery. (touch wood) :)
I like to keep BM's informed as it may help a member further down the line.
 

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