I have a 2001 F4i and one day about 3-4 months ago I went for a ride and about 2 minutes into the ride my bike died like it ran out of fuel but the tank was full. Figured the pump was bad so I installed a brand new pump and nothing changed. I checked the fuel cut off relay and it’s fine and working. The pink wire coming from the zener diode reads 8.2v (I don’t know if it has to read exactly 9v or not but I feel like if the diode was bad it would read 0v or even the full 12v) the wires that connect to the fuel tank read 12v. I even check the tip sensor but it appears the owner before me already did a tip sensor delete basically permanently jumping the tip sensor. I’ve jumped both the old and new pumps and they both work just fine, at this point I don’t know what else it could be and if you have any ideas I would love to hear them

 

Welcome to the forum Bmk, it might be something as simple as the engine stop switch malfunctioning.
These are prone to causing the sort of problem that you are describing.

 

Do you have spark?

Most likely not bad part anywhere, just loose/broken wire or corroded terminal in connector somewhere. Pull out meter and measure. This is 5-minute fix with meter, or less in many cases. Then do these tests.

1. Connect trickle-charger to battery.
2. Key ON
3. start/kill switch -> RUN
4. pull headlight fuse to prevent draining battery.

5. measure resistance between fuel-pump connector grn-wire terminal and chassis-ground, ohms = ???
6. measure resistance between engine-stop relay activation-coil red/wht wire to chassis-ground, (not bigger red/wht power wire), ohms = ???
7. measure resistance between fuel-pump relay activation-coil brn/blk wire to chassis-ground, key OFF then ON, ohms = ???

Next, let's trace flow of electricity to fuel-pump starting at battery...



8. measure FI fuse input-power to engine-stop relay big red/wht wire. Should always have power. Volts = ???
9. measure voltage at engine-stop relay blk activation wire from start/stop switch. Volts = ???
10. measure voltage at engine-stop relay output wire blk/wht, volts = ???
11. measure voltage at fuel-pump relay's inputs blk/wht (both of them), volts = ???
12. measure voltage at fuel-pump relay's output brn wire, key OFF then ON, volts = ???
13. measure voltage at fuel-pump connector, brn-wire terminal, key OFF then ON, volts = ???


Numbers will tell exactly where problem is. No need to replace perfectly-working parts with brand-new perfectly working parts.

 

Have you checked the 20 amp fuse outside the main fuse box ?

 

So I checked every wire and the brown wire at the relay shows no volts and the brown wire at the fuel pump connector also shows no volts all other wires show 12 or more volts I just don’t know how to follow the wire to see if it’s not connected somewhere

 

If you have +12v on both blk/wht power-input wires on fuel-pump relay, but no output on brn wire, then some possibilities:

1. bad fuel-pump relay

2. no GRND from ECU on fuel-pump relay activation coil brn/blk wire. Could be broken wire. Did you measure ohms to chassis-ground??? Also measure that wire at ECU connector as well.

3. bad ECU

You're just ONE measurement from finding out what's wrong and fixing this (well, maybe two)...

 

Turned out to be 2 things 1 was that where the brown wire passes through the tank there was 9000 ohms of resistance so I took that green puddy stuff off and pretty much just pushed the wires down on the metal so they would make full contact and there was no more resistance. Then when I went to install the tank back on the bike the brown wire wasn't getting any power so I just jumped the power from the black and white wire to the brown wire on the relay and the fuel pump turned on. I’m pretty sure that means the relay went bad so I’m ordering a new one and hopefully it fixes my problems.

 

OK...