Originally Posted by Mark+4
Hi again,

Electrics were never my forte, but have been reading up and think I understand the reason why a Relay is required if I want to use the same/similar switch. So I think I need a 4 pin Relay set up like the diagram below, please someone confirm or set me straight.

[Linked Image]

I would take the live feed from the Fuse box and the "Light" would be my Fan.

Also...

Does anyone know if the existing switch can be made into a 4 position, there seams to be lots of unused connectors on the back, or do I need a replacement?
IF you should choose to use a relay, good idea to use one which has a flyback diode incorporated across the relay coil. This will minimise voltage spikes which could damage the ecu. They cost little more and, if you find one day that a relay has failed on perhaps your fuel pump, then this one could be borrowed to plug in to get you home.

Doug
2011 Plus 4 in Rich Maroon

1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900