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Hey guys, I have recently purchased a project 01 929. After putting some needed parts on it, cam pulsor, crank sensor, etc, when I turn the ignition and run button on the fuel pump will not prime. The fuel cut off relay clicks when I cycle the stop/run button (which is brand new). When I test the 3 wire plug that the fuel pump plugs into I get:

Green - ground
Brown with black - 11.8ish volts
Brown - nothing

When I direct wire the full pump from the battery, I out 12.7 volts to the brown wire and ground to the green wire and the pump runs. When this is happening the clear return line from the FPR is pushing fuel back to the pump housing. Is this right?


I've swapped out the high beam relay for the fuel cut off relay u der the seat by the tip over switch. I have the fairings off of the bike and the harness just laying on the front tire. Is there a sensor in the nose that needs to be upright? I thought the tip over switch u see the seat was meant to kill the bike in the event of falling over.

I also have an aftermarket ignition from eBay on the bike. The wires are not the same color as the factory ignition. But I do have 12.7 volts coming in on one wire and 12.7 going out only on one wire after the ignition is turned to on. The other 2 wires in finding out are ground and the other I don't know what it is for.

Any help is greatly appreciated.
 

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Search the forum for the infamous corrosion issue the 929 has with the orange terminal block that runs on the right side of the frame apart of the wiring harness.
 

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Hey guys, I have recently purchased a project 01 929. After putting some needed parts on it, cam pulsor, crank sensor, etc, when I turn the ignition and run button on the fuel pump will not prime. The fuel cut off relay clicks when I cycle the stop/run button (which is brand new). When I test the 3 wire plug that the fuel pump plugs into I get:

Green - ground
Brown with black - 11.8ish volts
Brown - nothing
A multi meter draws almost no current so even if you have a very high resistance in the circuit it will still read ~12v. To get a true voltage reading you test the voltage under load, i.e. with the pump connected (e.g. by back-probing the connectors).

In that state you'll probably find the voltage is close to zero. If you keep the positive probe on the brown/black and move the negative DMM connection to a known good ground (e.g. battery -ve) and you then get ~12v you know the problem is on the ground side, otherwise it's on the supply side (more likely).

At this point you simply need to follow the wiring back from the pump, measuring the voltage before every connector, fuse, relay etc. until you find the the component that's causing the voltage drop.
 
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