I know that the electrical part of the campervan build can be a little confusing for some but this one is a real brain teaser and even I have to pause and think about it occasionally.
The other day I was installing a new tap and pump system to a van and it had been a while since I fitted a water system – all of a sudden the brain went blank and I am staring at 3 sets of wires and feeling slightly embarrassed.
Thankfully, normal cognitive function resumed but this prompted me to create a wiring diagram to help others who may have the occasional brain-freeze.
So who is this post for? Well, if you have a tap with a microswitch and a submersible pump to bring water from your onboard tank when you turn on the tap then this post will help you wire it all together from a single live feed.
What equipment will you need?
- Tap with a microswitch
- Sumbersible 12v pump
- Fused live feed from your battery
- Ground wire from chasis or negative busbar
- 3 way connector block
You can run a live feed from your fuse box or use an inline fuse if running from the battery terminal.
What wire goes where?
Here goes:
Step 1: Connect your live feed from the battery to the positive wire from the tap (they should be labelled)
Step 2: Connect your negative wire from the tap to the positive wire of the pump
Step 3: Connect the negative wire from the pump to the ground wire from your negative busbar or chasis.
Wiring Diagram

Grab a copy of the wiring diagram in pdf format – simply complete the form below