Removing the 50 amp fuse

[Robert May]

Hello all,

I'm Robert May; a new MP owner from North Devon, I took delivery of an 18 plate 220 sport on Saturday as a mobile office and mile muncher for my business. According to the finance director the Marco Polo is a more appropriate business vehicle than the ex-police dualiner I converted a two years ago, my 'Vito vardo'. I did not take a lot of convincing.
During the briefest of introductions to the MP I was advised to remove the 50amp main fuse for the back end of the van when I'm not using it. This is apparently necessary to preserve and protect the auxiliary batteries. Is that correct advice? Are you all firkling under the seat to take out the fuse? I'm concerned that removing the fuse interrupts the charging system so the cells won't be getting charged. I have wandered through the manuals and can't find reference to this and wonder if something had been left on and had drained the batteries prior to the PDI and whipping the fuse out was their work around.

Your experience and advice will be very gratefully received.

Thank you in advance

Robert

 

[Explorer]

Picked up my MP 3 weeks ago. They missed to insert the 50Amp fuse (nothing was working from the command module) , but I found it the glove compartment with a note.
Yes, there is nothing in the manual, but the note described the location and I was able to insert the fuse.

In the note it also said that the fuse was removed to avoid draining the aux battery when shipped from Westfalia (and was supposed to be installed by the reseller).
I don't think the battery will be charged without the fuse. I will not try to get under the seat to get out the fuse, at least. Will keep my MP connected to the grid when not used.

 

[Robert May]

Thank you Explorer. I suspect the MP is new to the guys in the dealerships and they might be fudging their way through the handover. Now I have asked the question let's see if the experienced users have advice for us. From experience with IT cell packs, they don't like to be constantly on charge but don't cope with being flattened to exhaustion either

 

[Katie]

I would not remove the fuse unless the vehicle was going to be laid up for a long time. I guess Westfalia remove it as they don’t know how long the vehicle will be lying around at storage / docks / dealer etc.
If the fuse is not in you won’t be able to charge the leisure battery when driving
The leisure battery needs some care but not to that extent. Charging the van up on mains once a month should keep it in tickety boo condition.

 

[Katie]

Just thought - maybe the battery would be charged without the fuse in but still no point in removing.

 

[Robert May]

Thank you Katie, that was my thinking but when you're told something and warranties are voided if you don't do what you've been told you tend to what you've been told.
With my business head on, is there a feedback system from the forum back to Mercedes? They need to know if the hand over process isn't as strong as it should be.

Little things such as the continental to 3 pin adapter, the shower attachment from Westfalia, a set of mats. Under £100 of essentials left off a £55k vehicle is just a bit bonkers. Its not the money it's the inconvenience that's a disappointment.

 

[Katie]

I particularly agree about the mains socket. It wouldn't take much to put a UK one in for rh drive cars at the factory. Don't mind about the mats as we only need the front ones in rubber but I guess shower attachment may be handy.
Overall, however, the mp is a joy to drive and spend time in. Not tried the auto parking gizmo yet - too scared!

 

[Robert May]

I've had to buy a set of rubber mats as an extra.
I only have the manual autopark system. I automatically park it well away from everything else

 

[JP Lakedistrict]

Does anyone know, if the vehicle is plugged into the mains, will the main car battery be kept topped up as well as the leisure battery. I am away for lengthy periods, and in the past, with my normal everyday car, I have tended to leave on a trickle charge conditioner to keep the battery at the correct level.

 

[mptripsaway]

Does anyone know, if the vehicle is plugged into the mains, will the main car battery be kept topped up as well as the leisure battery. I am away for lengthy periods, and in the past, with my normal everyday car, I have tended to leave on a trickle charge conditioner to keep the battery at the correct level.

Yes, however I'm not sure if it is okay to leave vehicle on mains for extended periods, maybe someone else can answer that?

 

[mptripsaway]

Does anyone know, if the vehicle is plugged into the mains, will the main car battery be kept topped up as well as the leisure battery. I am away for lengthy periods, and in the past, with my normal everyday car, I have tended to leave on a trickle charge conditioner to keep the battery at the correct level.

Copied direct from manual.........

If the following conditions are fulfilled, the battery charger also charges the starter battery of the vehicle:
the voltage of the starter battery must be between 9.5 V and 13.85 V
the voltage of the additional battery must be at least 13.9 V

This is an auxiliary charge (4 A) which compensates for the self-discharging of the battery and which ensures that the vehicle can be started. The starter battery is not fully charged.

 

[MPman]

New to this forum and on it because our auxiliary battery appears to have just died. Dusted the MP off for a trial run yesterday before taking it round Scotland in a couple of weeks and the control unit wouldn’t turn on. Hooked up to the mains and it flickered several times then came on showing the battery at 5.8 volts. Then it died again. Took the van for a 90 mile run, still no display. Hooked up again on return and it repeated the flickering on and dying process. Got up to 6.4 volts then dropped to 5.8 volts and the control screen went blank ..... checked the manual and discovered that if the the battery isn’t charged up every four weeks or discharged heavily over an 8 week or more period it can be irreparably damaged. The MP has been laid up for a couple of months so I’m guessing the battery’s had it. Does that sound like the problem with these symptoms? No warnings given about this on picking the MP up, no one had been trained yet they told us, we’ve since been learning as we go. The other thing we had to track down after delivery was inserting the fuse to get the water pump working for the tap, that was in the glove box!

 

[Anton]

New to this forum and on it because our auxiliary battery appears to have just died. Dusted the MP off for a trial run yesterday before taking it round Scotland in a couple of weeks and the control unit wouldn’t turn on. Hooked up to the mains and it flickered several times then came on showing the battery at 5.8 volts. Then it died again. Took the van for a 90 mile run, still no display. Hooked up again on return and it repeated the flickering on and dying process. Got up to 6.4 volts then dropped to 5.8 volts and the control screen went blank ..... checked the manual and discovered that if the the battery isn’t charged up every four weeks or discharged heavily over an 8 week or more period it can be irreparably damaged. The MP has been laid up for a couple of months so I’m guessing the battery’s had it. Does that sound like the problem with these symptoms? No warnings given about this on picking the MP up, no one had been trained yet they told us, we’ve since been learning as we go. The other thing we had to track down after delivery was inserting the fuse to get the water pump working for the tap, that was in the glove box!

This sounds pretty much exactly like our symptoms, however we were able to charge it by connecting to main. But, the battery goes empty very quickly, so something is wrong. And now, after the car was at a repair shop (self inflicted damage..) for a couple of weeks, the battery doesn't charge at all when connected to main.
I'll contact a MB repair shop next week, I'm assuming they will tell me the battery needs to be replaced.

(Connect to main once a month like some owners are saying would not work for us, more like once or twice each week in order to keep the battery alive.)

Can anyone tell me where the 50A fuse is located? Can't see it under the drivers seat, guess I'm looking at the wrong place?
Nevermind, I found it by removing the plastic cover on the outside of the drivers seat. And all fuses look ok...