Water pump or tap switch problem?

[jliungman]

Hi!

I thought I had frozen my fresh water pump during my first winter of ownership in Scandinavia. I was not getting any water, basically. Checked the fuses (OMG just finding those was major carnage, and figuring out what fuse was what... wow). Managed to open the water tank (THAT was a battle, including designing a home-made tool), got the pump out, then connected it directly to a 12 V battery. It then runs just fine. And it pumps water properly (got wet trying THAT).

I now assumed a glitch where the pump is connected to the power supply (little plug on top of tank, supplied by the relay in the tap), but this cable shows the normal 12 point something volts when I open the tap (no pump connected), so the relay seems ok. Tried bypassing the plug completely. Yet the pump still does not run from that power source.

*add major head-scratching here and a big mug of coffee*

So:
a) the pump itself is ok with a reliable power source
b) I can measure voltage from the supply cable when the pump is disconnected and tap is on
c) I measure very low voltage in the supply (0.5 V) as soon as I connect the pump, and the pump does not run.

Is it possible that the relay (micro switch?) is semi-glitchy, providing the voltage when there is no load, but with a poor connection such that it cannot power the pump? In other words, a voltage drop under load, due to high resistance. I seem to hear the pump ticking and sort of almost starting to turn. If I did not know that the pump runs fine with a proper 12V power supply, I might have suspected that it has shorted out (but that SHOULD have blown fuses in my experience).

Any ideas, all you clever people out there? I know 12 volt systems from boats, but only ever had pressure-sensitive pumps, not taps with a relay.

Thanks

John

 

[flying banana]

tap micro switch contacts under the sink may just need a clean ? take the drawer out and have a look there

 

[WelshGas]

Hi!

I thought I had frozen my fresh water pump during my first winter of ownership in Scandinavia. I was not getting any water, basically. Checked the fuses (OMG just finding those was major carnage, and figuring out what fuse was what... wow). Managed to open the water tank (THAT was a battle, including designing a home-made tool), got the pump out, then connected it directly to a 12 V battery. It then runs just fine. And it pumps water properly (got wet trying THAT).

I now assumed a glitch where the pump is connected to the power supply (little plug on top of tank, supplied by the relay in the tap), but this cable shows the normal 12 point something volts when I open the tap (no pump connected), so the relay seems ok. Tried bypassing the plug completely. Yet the pump still does not run from that power source.

*add major head-scratching here and a big mug of coffee*

So:
a) the pump itself is ok with a reliable power source
b) I can measure voltage from the supply cable when the pump is disconnected and tap is on
c) I measure very low voltage in the supply (0.5 V) as soon as I connect the pump, and the pump does not run.

Is it possible that the relay (micro switch?) is semi-glitchy, providing the voltage when there is no load, but with a poor connection such that it cannot power the pump? In other words, a voltage drop under load, due to high resistance. I seem to hear the pump ticking and sort of almost starting to turn. If I did not know that the pump runs fine with a proper 12V power supply, I might have suspected that it has shorted out (but that SHOULD have blown fuses in my experience).

Any ideas, all you clever people out there? I know 12 volt systems from boats, but only ever had pressure-sensitive pumps, not taps with a relay.

Thanks

John

R kitchen cupboard. Remove cutlery draw. Locate underside of tap and follow wires to a plug. Disconnect plug and short the 2 contacts in the plug Not connected to tap. The pump should run and water out of tap if tap open.
If so then tap microswitch is port of call. May need cleaning or whole tap replacing.
To disassemble, plug in sink and pull of the the tap handle. It is a push fit.

Good photo of tap microswitch please

hi all. My switch needed cleaning and the springy bit fell off.. anyone got a photo of how it is assembled? even info on removal/exchange the switch would be awesome.. can u buy/remove just the switch? I see one photo on the forum but its blurred! I really dont wanna change the tap.. looks...

vwcaliforniaclub.com

 

[jliungman]

R kitchen cupboard. Remove cutlery draw. Locate underside of tap and follow wires to a plug. Disconnect plug and short the 2 contacts in the plug Not connected to tap. The pump should run and water out of tap if tap open.
If so then tap microswitch is port of call. May need cleaning or whole tap replacing.
To disassemble, plug in sink and pull of the the tap handle. It is a push fit.

Good photo of tap microswitch please

hi all. My switch needed cleaning and the springy bit fell off.. anyone got a photo of how it is assembled? even info on removal/exchange the switch would be awesome.. can u buy/remove just the switch? I see one photo on the forum but its blurred! I really dont wanna change the tap.. looks...

vwcaliforniaclub.com

Awesome! This worked like a charm, and apparently I was on the right theoretical track. Also, initially not knowing about the micro switch provided me a great learning experience: locating fuses, identifying and cataloguing what each fuse does (the manual was all wrong), learning how to open the water tank and building a tool, cleaning the tank, learning how my pump works... All in all, a great day! Thanks, and thanks also to @flying banana!

 

[Manya]

tap micro switch contacts under the sink may just need a clean ? take the drawer out and have a look there

I have the same issue as the one above. I've bought a new pump for a competent person to install (not me) but trying the micro switch seems like a good place to start ahead of the excavations to get at the water tank etc. EXCEPT I don't know what a micro switch looks like. can you describe it for me, or post a pic? Thanks

 

[WelshGas]

I have the same issue as the one above. I've bought a new pump for a competent person to install (not me) but trying the micro switch seems like a good place to start ahead of the excavations to get at the water tank etc. EXCEPT I don't know what a micro switch looks like. can you describe it for me, or post a pic? Thanks

The microswitch is within the tap which has to be disassembled.

 

[BubbleBus]

hiya, i put some photos of our tap switch insides a little while ago...search for .... tap not working. basically a small springy bit of metal that flicks two contacts apart (tap off) or allows them to connect (tap on)

 

[Manya]

hiya, i put some photos of our tap switch insides a little while ago...search for .... tap not working. basically a small springy bit of metal that flicks two contacts apart (tap off) or allows them to connect (tap on)

Thank you - that’s really helpful

 

[Maxi-Mizer-T6]

This (and a few other threads) were of great help, as I've had 3 different issues already with the water system in the California. I've learned a few things as I fixed all of them, including replacing the water pump myself, so I decided to document it all in case it helps others. Here's a first guide on how to identify which problem you are actually experiencing:

https://medium.com/@maxi-mizer/fix-vw-california-ocean-coast-kitchen-water-issues-43a19d0d893a

I hope it helps! I'll update this thread as I complete the detailed step-by-step guides (feel free to drop by that article and give me some claps and comments for motivation!)