Hi,
The fuel pump relay supplies the +12volts to the fuel pump if all conditions are satisfied i.e sidestand switch etc. If your measuring +12 volts at the fuel pump connections then in theory the relay is okay. However the pads of switched relays become pitted with time resulting in, effectively a dry joint which shows up as a high resistance. Basically if unloaded can easily measure 12volts (similar to unloaded batteries) but when loaded by the pump causes all the voltage to drop across the pitted relay pads. If your measuring the voltage with the pump installed then the chances are it's the pump. One final test before I would replace the pump would be to short out the switched connections on the relay socket. If it still doesn't work then I would try to run flying wires from the battery directly to the pump interconnect. This would eliminate the wires in the loom.
Hope this helps.
Geoff
Threaded Mode