I have a 2000 CBR929RR i purchased from a friend but its a project bike. The motor has new valves and a new head, and was put together by someone else. I got the bike and the fuel pump will not prime but the fuel pump did work with 12v jumped to it until last night when it stopped doing that and i found a sponge inside the fuel pump, so i ordered a new pump kit online. I was messing with my multimeter and found the brown/black wire off the fuel pump plug has 12v, the brown has nothing. I have checked for codes and nothing happens. Ive jumped the BAS and when i do, the relay will click so im guessing the BAS is good? I do have a PC3 installed and when i turn the kill switch off, the PC3 shuts down, when i turn the switch on, PC3 comes to life so i would imagine the switch is working. Im not sure where to really start from here, is there a way to test the ECU with a multimeter? should there be any voltage on the solid brown wire?

 

Hi the test for the fuel pump through the 3pin connector is between Brown and Green , the Brown/Black wire is the Fuel Reserve Sensor wire. Have a look at the fuel cut relay

 

I did check the brown/black wire on the 3 pin plug and it has 12v when i turn ignition on, with ignition off it slowly drops down to nothing, i tested ignition on and kill switch on then off with same result

 

Here

 

I have the honda service manual book, cost me $100 but i got it. I plan to look it over more tonight but thanks for that photo you attached. I ordered a new fuel pump kit online so once i get it ill put a new pump in and see what happens. Then the next will be getting all the lights, plastics, and the bike all together again.

 

Try using the headlight relay in place of rhe fuel pump cutoff relay. Mine was doing the same thing and that solved the problem.

 

I got a brand new fuel pump and installed it, and i got a new relay for the fuel cut off and put that in. I am still not getting fuel prime. I looked at the service book and it shows 2 grounds for the ECU which i checked and are grounded. I checked the wire from the ECU to the fuel pump and it has nothing, no voltage. I put 12v right to the pump and it kicked on. I have a PC3 installed that turns on and off with the kill switch and ignition, so im sure the switch is fine. I have tried to bypass the tip sensor and this didnt fix it, i also shook the sensor and it sounds like a liquid is inside? I have a FI light on dash and a red light, but when i try to pull codes im still getting nothing. Is it possible the ECU is bad? Or could there be something else im missing here?

 

I forgot to mention, there is 12V going to the sensor on the pump for low fuel, but theres no voltage to the main power wire to the pump.

 

What have you got from the Fuel cut relay on brown/black to the ECM with ignition on, and have you tried the headlight relay swap with the Engine stop relay

 

i checked both relays, both have 2 black/white wires, 1 relay has 2 black/white wires together, and all are reading 11.8v