Water pump not working

[PhilipHa]

I am about to go on holiday and neither the sink tap or shower is now working. I have been through the previous forum threads but can't find an answer which matches the issue:

• the problem occurred last time I went on holiday, tap wasn't working but restarted spontaneously just before I left so I ignored the problem
• the shower hasn't been working for some time (no water coming out, pump not making a noise with switch on)
• the fresh water level indicator has never really worked

So far I have done the following:

• the tank is full of water, it has been left full for the last month since I last used the van, didn't both emptying it
• I can't hear the pump running with the tap switch on/open (turned to right), but there is a click when the switch/handle on the tap is moved
• fixed the water level indicator (a bad design, it relies on a float in the tank, but the hose for the pump was fouling on it stopping it going up and down), its now indicating full on the LCD at the front
• checked the connectivity of the tap under the sink - the wiring shorts when turned on, so am assuming its working, and clicks when moved right
• checked the voltage going to the pump, always 0V, never goes to 12V even with tap switched on, so am assuming the problem is upstream of the pump
• the water pump fuse (no. 2) is ok, taken it out, visually inspected it, check continuity across its terminals. I have not had any fuses fail in 18 months of owning the van
• all lights, fridge, roof etc. in the cabin are working, leisure battery voltage good at 14.3V (the van has solar PV)
• the online manual says that the shower won't work unless the tank is fairly full, but there is nothing in the manual to say the kitchen sink won't work if the tank is near empty, so am assuming there may be some form of control module or relay detecting the tank level controlling whether the shower pump gets switched on?

Given this happened before my last holiday and it then resolved itself with no intervention from myself I am assuming it might be an intermittent connection somewhere? Its never happened when I have been on holiday so am assuming it is precipitated by not using it for a few weeks.

Does anyone have a wiring diagram for the campervan bit of the Marco Polo or can suggest where I can find one? Or know whether there is a control module or relays between the tap/switched and the pump? Or do you have any other suggestions?

I plan on taking a portable water tank with me on holiday and resolving when I get home.

 

[DogWagen]

I can't help with a wiring diagram but I'm wondering if either the pump has seized or if there is a short to earth in the supply line. Also worth a a look at the German MP facebook page (marcopolomylife) - you might get some more ideas there.

 

[enano]

Possibly obvious, but can you measeure +12V in the fuse terminals? You can remove the grille under the fridge, around the pump fuse and check the connections in the wiring harness behind.

If you ever get a wiring diagram, please let us know.