Dead MP?

Le Patron

New Member
Hello and Happy New Year! No it's not a political rant about my MP, or any other politician, I just wanted to know if any other good Marco Polo owners on here have had a similar problem? I am a new to the MB, MP world and purchased a nearly new MP V300D on a 23 plate with 3,500 miles from new back in June last year. We've been out on four short UK camper expeditions so far, with the goal to know the vehicle basics before venturing further afield for longer trips. Everything has been fine, except for a failed rear tailgate lock, that MB Gloucester replaced under warranty after a wait for the new parts. The lock failed whilst camping away and when I rang MB assist, a very nice German speaking man said he would send out a recovery truck to take to the nearest MB truck dealer as the vehicle really comes under that service area. (* I'm aware of other comments that the MP seems to fall between the two MB divisions for service). I declined the recovery option as we could still gain access to most of the rear contents and carry on camping. Once home I rang a MB truck service centre at Redditch, to ask about the tailgate lock service, they said the MP needs to go to a car dealer franchise... and so it did, but I am aware that they are not too knowledgeable about the MP in general.

For my next little problem, that is current, or rather the lack of it... the Marco Polo is totally dead. The car has been sitting under cover for three months and I thought I would give it a road trip to clear the cobwebs and put some juice back into the system. Unfortunately the vehicle is totally dead, no response or sign of life at all, neither set of keys, new 2025 batteries or skeletal keys allow access. I haven't knowingly left anything on, the auxiliary battery was charged 75% the last time the engine ran in early October. I am surprised that it is absolutely dead to the world. I checked the online manual and thought I best open the MP and take out the main battery, bring it into the warmth and put it onto my CTEK MXS 7.0 battery charger to see if it will charge or now indeed hold a charge. Unfortunately, I cannot open the vehicle at all.

I rang the Gloucester MB service dept and was only able to ask their receptionist to ask a tech what to do, although explaining what I had already tried, the answer was to "try the skeletal key in the passenger door once I had prized off the blanking plastic to reveal the lock, pull open the bonnet as the latch is in the passenger footwell and jump the battery in the engine compartment. Otherwise ring for roadside assistance".

On newer MB cars there are lock covers to be prised off, but not on my MP, just a one plain to see key entry on the drivers side. Also the MB-MP online owners manual states that you shouldn't jump start the vehicle if the battery is completely dead as it could cause a hazard as it may of frozen, may not hold charge at all etc., etc. All possibilities - if only I could gain entry to the vehicle.

I could call for assistance, though whoever turns up to my remote house location, will still need to open the MP, release the brakes, put it into neutral just to drag it onto a recovery vehicle and be taken on for more head scratching. The only positive is - I don't need to drive it or go anywhere for a couple of months and would dearly like to know if there is a way to open it, beyond what I have tried, then I can take out the main battery and charge or even replace it if needs must.

Can anyone steer me in the right direction? Many thanks in advance.

 
Sadly almost any modern vehicle left for several weeks, let alone months - especially more sophisticated cars like Mercedes etc - will result in a flat starter battery because there are always systems running (alarms at the very least) that gradually drain the battery.

The advice you have been given is sensible - but the easiest would be to call Mobilo (assistance) and have them do the work on your behalf. They may also be able to assess the battery state (both the starter and leisure batteries won't take kindly to being discharged for a long period).

The MP does have an aid to all this though in the form of the mains hook up....if you connect this while the van is not use (even intermittently ), not only will you keep the leisure battery in good condition but once that's topped up it will trickle charge the starter battery too. We have ours on a timer overnight a few time a week and so far that seems to have done the trick.

The good news is that I doubt there is anything actually wrong with your MP beyond the flat battery.

Hope this helps?
 
Get a jump start to get you going
Keep the main battery on a CTEK when not used for more than 5 days
Keep the leisure battery charged by hooking up permanently whilst not in use (if the LB is not kaput due to prolonged no charge periods).
This has worked fine for me since 2018
 
Unfortunately all modern cars drain batteries to some extend as lots of things are running all the time.
The MP has 3 batteries: main, leisure and auxilliary. The aux battery can unlock the parking brake, so there is some chance you can unlock it to get it towed it you can get into the van.

The external 230V connector powers an AC-DC charger that feeds the leisure battery. Once the leisure battery is completely full it will trickle charge the main battery - but only if it is within a certain voltage range. It won't hurt to try.
When I don't drive the MP for a few weeks I plug it for a couple of days and never have had a problem.

What is the exact problem with the physical ("skeletal") key? It should unlock the door mechanically and work even with no battery present. They tend to get stuck due to dust and lack of use, but nothing that some grease spray cannot fix.

If in the end you have to get your vehicle towed, many tow trucks are equipped with jack skids - that's how they remove badly parked cars. Just tell them your parking brake is stuck before calling.
 
Hi Le Patron

What's been said already is predominantly true. As well as the MP, I have a 350 GLE SUV, VW Amarok and a BMW IX. All of them can be a pain if not run locally for 20 mins every couple of weeks! However for the MP its simple

Just run an extension cable or plug the camper lead into your garden sockets and leave it for a couple of days.... If all goes to plan it will be back to normal. If it isn't then phone Mercedes Mobilo and use what you have paid for.... MB service. They will do all the hard work and arrange for whatever needs to be done. If it needs to leave your home they should provide a loan vehicle, and if it doesn't they should fix it under warranty.

Good luck and let us all know how you got on

Richard
 
Not a nice start to owning a new vehicle. Hope you get it sorted.
I completely agree with what RichnNat has said. Put it on hook up and see if it wakes up.
If not call out MB Service (RAC breakdown will probably turn up) and let them solve the problem. They may have to take it to the dealer anyway.to get the batteries checked. The leisure batteries don’t take too kindly to being left discharged for a long time. . A problem seen from posts here with secondhand vehicles because they have been left on dealer’s forecourts until sold.
As someone who remembers the days of requirements for parking lights for obnstreet parking I was forever having to charge up car batteries especially in winter.
That was a thing of the past until recently but now I am frequently nagged by car apps and told to drive the vehicle because the battery is going flat.
All my new cars have to be connected to trickle chargers if away for more than a few weeks. The old ones can be left for months. So much for modern technology and “progress”.
 
I live abroad and normally have my MP charged via the hookup. That was fine until I had my driveway paved. The MP refused to start after a couple of weeks parked without charging. Fortunately, I removed and recharged the battery (I had to piggyback it with another battery initially). It is still working after 5 years. To ensure I don't find myself in the same position again, I have fitted a solar panel on the roof which charges both batteries. It's a very easy kit to install, with no drilling and simple instructions to follow. I bought it from https://www.solarcampersolutions.com. Well worth it for me.
 
Hello and Happy New Year! No it's not a political rant about my MP, or any other politician, I just wanted to know if any other good Marco Polo owners on here have had a similar problem? I am a new to the MB, MP world and purchased a nearly new MP V300D on a 23 plate with 3,500 miles from new back in June last year. We've been out on four short UK camper expeditions so far, with the goal to know the vehicle basics before venturing further afield for longer trips. Everything has been fine, except for a failed rear tailgate lock, that MB Gloucester replaced under warranty after a wait for the new parts. The lock failed whilst camping away and when I rang MB assist, a very nice German speaking man said he would send out a recovery truck to take to the nearest MB truck dealer as the vehicle really comes under that service area. (* I'm aware of other comments that the MP seems to fall between the two MB divisions for service). I declined the recovery option as we could still gain access to most of the rear contents and carry on camping. Once home I rang a MB truck service centre at Redditch, to ask about the tailgate lock service, they said the MP needs to go to a car dealer franchise... and so it did, but I am aware that they are not too knowledgeable about the MP in general.

For my next little problem, that is current, or rather the lack of it... the Marco Polo is totally dead. The car has been sitting under cover for three months and I thought I would give it a road trip to clear the cobwebs and put some juice back into the system. Unfortunately the vehicle is totally dead, no response or sign of life at all, neither set of keys, new 2025 batteries or skeletal keys allow access. I haven't knowingly left anything on, the auxiliary battery was charged 75% the last time the engine ran in early October. I am surprised that it is absolutely dead to the world. I checked the online manual and thought I best open the MP and take out the main battery, bring it into the warmth and put it onto my CTEK MXS 7.0 battery charger to see if it will charge or now indeed hold a charge. Unfortunately, I cannot open the vehicle at all.

I rang the Gloucester MB service dept and was only able to ask their receptionist to ask a tech what to do, although explaining what I had already tried, the answer was to "try the skeletal key in the passenger door once I had prized off the blanking plastic to reveal the lock, pull open the bonnet as the latch is in the passenger footwell and jump the battery in the engine compartment. Otherwise ring for roadside assistance".

On newer MB cars there are lock covers to be prised off, but not on my MP, just a one plain to see key entry on the drivers side. Also the MB-MP online owners manual states that you shouldn't jump start the vehicle if the battery is completely dead as it could cause a hazard as it may of frozen, may not hold charge at all etc., etc. All possibilities - if only I could gain entry to the vehicle.

I could call for assistance, though whoever turns up to my remote house location, will still need to open the MP, release the brakes, put it into neutral just to drag it onto a recovery vehicle and be taken on for more head scratching. The only positive is - I don't need to drive it or go anywhere for a couple of months and would dearly like to know if there is a way to open it, beyond what I have tried, then I can take out the main battery and charge or even replace it if needs must.

Can anyone steer me in the right direction? Many thanks in advance.

You could just attach a cable to charge your leisure battery through the outside charging point. Once the leisure battery is full it switches to charging your starter battery.​

 
So an update a long last, all is well and the van is back up and running. The first problem with the locks, or should I say the only key ‘lock’ on the drivers side and using the skeleton key, I reverted to using a pair of big pliers to twist the key back and forth after lubricating and finally, just as I thought it might snap off - it worked open. Next I couldn’t open the passenger door manually, to open the main battery cover, luckily that opened once I placed a set of jump leads and life came back to the van. There wasn’t enough juice to start the engine, all the dash lit up and after waiting five minutes for some charge to cross over I turned the ignition key waited for the glow plug coils to go out and - nothing all went blank until the key was released again. So pulled the main battery out, recharged via CTEK MXS 7.0 charger, no difference, then pulled out the leisure battery. That measured 50% charge and topped it up to 90% and reinserted. Checked all fuses and starter relay, jump leads back on and waited 5 mins, tried the ignition and a one second response from the starter… tried three more times and engine fired up. Left it running 30 minutes whilst I rest doors, windows, mirrors and all other checks then after warming fully. Turned it off. Started again two hours later. Hopefully lesson learnt. Leaving it on trickle charger tails and watching battery levels more closer… as with stored motorbikes. Chargers now everywhere! Thank you one and all for help and advice… until we meet again!

IMG_0490.jpeg

IMG_0488.jpeg
 

Marco Polo Club

Back
Top