W447, v220d 2017 agm battery issue.

[Nigel Griffiths]

Another post about my new to me, v220d, I've only had the car a couple of weeks, but here goes another question issue. The car was delivered to me, about 3 weeks ago, it was left parked up for about a week, before I thought I would go for a run. Didn't know anything about start stop system on it, never had a car with it. Anyway on the short journey, I noticed it wasn't starting stopping. Now Ive found out that there is a automatic symbol, that glows green when it's working. Tried unlock the car, on Friday night, battery completely dead, had to use the secret key to get in. Managed to get the bonnet open hook up a ctek charger to remote battery terminals, to start charging. Left overnight, came out in the morning ctek charger in error mode. Used a normal charger, and left that charging all day Saturday, and all night. Battery fully charged Sunday morning. Went for a 9 mile drive, start stop working! Parked up to go for a 2 hour walk with kids in a park. Got in the car, drove off, start stop not working. Yellow automatic sign never went green. Tried to get in the car tonight, completely dead again.

Do you think the agm battery is knackered or is it the auxiliary battery that's knackered or both?

Any thoughts?

 

[Nigel Griffiths]

Whats really annoying now, went to the car this morning to use the secret key, even that doesnt work. There isnt enough charge in either battery to power the lock. What do I do now? On American Merc garage website, they suggest jacking up the car, trying to find the solenoid, and then connect another battery to get some power in to it. I bet thats not easy to find, and whether its accessible from below the car is another matter altogether.

 

[Tony Dyson]

By "Secret Key" do you mean your metal key hidden in your electronic Key Fob? This key opens the lock mechanism manually not by any other assisted means, perhaps you just need to squirt some lubricant in the lock, or apply some heat to the key if frost or ice could be an issue? mine does need some robust treatment at the best of times.

 

[Nigel Griffiths]

Hi Tony, yes that the key. I think on new cars the drivers side door lock is still operated by a solenoid lock. The key turns in the lock, but it does nothing. There is no resistance when you turn the key. On friday when it first happened, it did open, but I lock it, by mistake but he battery was on charge, out first it didnt open, but went back to the car when it was on charge and it had popped open. Rather strange!

 

[Tony Dyson]

Well I'll stand corrected! I thought the metal key was designed to get into the car in the event of a loss of power or vacuum and was entirely mechanical! If you don't have another door with key access you can try then applying a 12v supply to the supply terminal on your starter motor from underneath would be an option, keep your fob in your hand, touch the right terminal and use the fob to unlock the car.

 

[Nigel Griffiths]

Yes i thought so as well, and thats what happens on my old viano. What's the point in having them! Come on mercedes, they are going backwards. I would have thought

 

[jimbg]

I would suspect that battery, if the Ctek gave an error then you have to wonder why?

 

[Nigel Griffiths]

AA, turned up last night, eventually they put power through the alternator connections, so we could get access to the car. Battery now out, waiting for a new battery to be delivered. He did say, that he thought there was a fault on the emergency lock, and it should unlock from that key. He reckons that linkage may have come off internally within door.

 

[Tony Dyson]

Result and a quick look in the door should identify a missing link, or not?

 

[Nigel Griffiths]

The saga continues. Brought a new battery, installed it this Saturday, after a full charge with CTEK charger, fine Sunday, Car is dead flat this morning!!!!!! I was suppose to be taking it to a main dealer for a service today, but now I cant. Emergency key still not working. AA called out, just waiting. Mercs want an extra £120.00 to do diagnostics on it. Im now taking it to my local indie. He reckons that MB will not allow them to upload service records to their main computer, their Digital Service Booklet. But on here it reckons that they can register to do this:

https://tools.mercedes-benz.co.uk/c...tradepartner/TradePartner_Digital_Service.pdf

 

[Tony Dyson]

Your local indie clearly ISN'T an (Independent Mercedes Specialist) as generally understood by MB and this forum, where are you based? I'm sure the forum members will advise known "Indies" who will know their way around the car and have access to Star diagnostics and be able to update the DSB if needed.

 

[Nigel Griffiths]

They have star etc, and all they do is merc vans, so more specialist than the normal merc indie

 

[Tony Dyson]

They have star etc, and all they do is merc vans, so more specialist than the normal merc indie

Who are they? and their business address?

 

[Nigel Griffiths]

They are called Best Quality Parts. The are linked to SMB Commercials.

Best Quality Parts

bestqualityparts.com

SMB told them they couldnt upload service records. I have actually sent them a link to the B2B Mercedes website, which they are now looking into. They probabley charge the indie a fortune. I bit like £120.00 per hour for diagnostics at a main dealer!

 

[Nigel Griffiths]

Tony, after I sent them the link, on Monday, Dave at Best Quality Parts has just told me that they can now upload service records to the Merc MSB system. Whilst he was looking at the system, he downloaded the service history for my new to me car. Very enlightening.

Anyway going back to my original point, as update, AA came out, took the under tray off and gave it a feed to so I could get in the car. We jump started the car, took a couple of minutes to get enough charge in the battery to it start. Left it running stationary so there was a bit of charge, and went for a 10 min 30mph round the block spin in it. Guess what - the stop start starting working, indicating that there was enough charge in battery. Anyway parked the car up, left the bonnet on the latch overnight, and I was totally expecting that the battery would be flat in the morning and I would need to jump it. 9.00am, started the car no issues, drove to the indie 5 mins down the road, start start was working. Its been in the indie garage 2 days, and guess what the battery hasnt gone flat. The Garage advised when it went to sleep, eventually after 30mins, the system was pulling 0.4 of amp which is nothing.

What is really strange is that I wouldnt expected a completely flat battery to become fully charged with it being charged by an alternator for less than 60mins.

The indie has also taken the door card off, and they said that Merc's had changed the system from the old Vito's in regard to the emergency key operating rod and he couldnt really see why my rod had come of the end of the emergency key lock. He had to drill out 20 rivets to get to the lock and locking mechanism. he has order new plastic part that connects the rod, from merc's which is luckily only £30.00.

 

[Nigel Griffiths]

Further update. The mechanism for emergency key which has totally changed from the W639 models has been replaced. There was some overspray on the one that was removed. This tends to suggest the door had been damaged previously, and this may have damaged the emergency lock mechanism.

The car is still in with indie. he did experience the battery going flat once whilst it was in there, and was drained in 3 hours. They recharged the battery and its still in garage, just sitting waiting for it go flat, as every time they test it, there is no parasitic battery draw, and all the modules go to sleep after 30mins or before.

Would a faulty aux. battery cause the main battery to go flat? If it was then I assume that it would constantly go flat and you see the draw on ammeter quite clearly.

 

[Nigel Griffiths]

Update: It must have been the faulty emergency lock mechanism that was triggering the car to 'stay alive' and not for it not to go to sleep. Its been fine since the indie changed the emergency locking mechanism, and battery hasnt gone flat.