Well if you can here a relay working then power is getting to that point. Can you then work on from there. Is not this component fitted right by the pump if it is coming from the tank?
There’s no switch as such in the tank. If you can here something, then it could be the pump stalled and trying to turn? Trying another tank with no luck, would sound like a power issue. Have you checked for power at the connector? There’s 4 cables on the connector. The two slightly thicker ones are the pump feed. The relay for the pump is under the seat. It’ll have brown and brown/cables connected to it. Whenever you have issues with fuel pump, injectors or coils it’s always worth fitting a new one. They cost a few quid and are responsible for the 12v to all three circuits. The circuit also relays on the side stand interlock circuit. Make sure neutral light is lit. You can bypass the side stand with a short between the two cables on the connector, loom side.
As well as the relay check the fuse/fuse holder. The fuel pump fuse holder on my 916 melted - the whole thing, fuse included was a glob of molten plastic. Oddly the fuel pump was still working as the actual metal part of the fuse was intact, I had to cut it out fit a new fuse holder assembly.
No it's a single in-line fuse holder under the seat (at least it is on a 916) with a 16A (IIRC) fuse in it. There are actually 2 side-by-side on my bike but the other has a smaller fuse. I don't know if/where this would be on yours but I assume there is a fuse as the pump draws quite a current and runs continually, would guess it's near the relay?
Probably the case. Check for 12v at the pump connector to make sure power is getting there, of the 4 wires, two will be for the pump and the other 2 for the low fuel sender, would assume (like 916) that the pump wires are the the thicker ones but a wiring diagram should be easily find-able online.
Looking at that pic, I'd say the brown/white is the positive to fuel pump and the black the negative/earth (how it is on 916), if so you should have 12v across them when the fuel pump relay is on. Presumably relay comes on for a few seconds when you switch ignition on and then goes off unless the engine is running? Try checking continuity on the wires: black to earth and brown/white back to the relay and then from relay to fuse to power.
The fuel pump should also run while the engine is cranking. if the relay is energising (clicking), it means that the ECU is operating it. You should also be able to check using JPDiag, if you have it, by testing the ECU output for the fuel pump (In your post showing the underseat wiring, the The 3-pin plug with only two wires in it and the cap covering it is the diagnostic port). Have you tried bridging the larger terminals of the fuel pump relay holder using a wire with 2 x spade connectors on it - to see if the fuel pump works or not? Where are you based, Martin? Maybe someone near can help?
You'd just need a short length (50mm would do it) of a suitable length of wire with some crimp-on spade connectors. Similar to this:- https://www.halfords.com/workshop-t.../halfords-spade-connectors-hef515-15-amp-male Remove the relay, bridge the High Tension connections (the BIGGER ones, i.e the ones that connect to the fuel pump connector - do NOT bridge the ECU side of the relay connector). When the ignition is switched on, the circuit will be activated, and you should get 12V to the fuel pump connector under the tank. One other thing to check - I have had the female terminals in these AMP Superseal connectors "relax" and not grip the male counterpart - resulting in no power to the components. This can be fixed by popping out the terminals from the housing and bending them back into shape. it can be checked by inserting a sewing needle or pin into the female terminal - if it falls out the connector is too loose.
Fuel level sensor doesn't click. If you're getting a click/clunk - the pump is gummed up and can't turn. Has it been sat for any length of time with old fuel in?
