04 cbr 600 f4i fuel pump not priming

[Bocephus5781]

Help! I've been trying to get my bike up and running and I've been having some starting issues. I changed the wiring harness to a brand new OEM wiring harness. Started fine. Started installing lights and somewhere between messing with that the bike decided it didn't want to start anymore. Everything acts normal except the fuel pump is not priming when the key is turned/ kill switch is flipped.... When I bypass power from the battery to the pump it runs continuously. The relays are brand new (even tried the old ones)... The engine stop relay clicks and works properly (as far as I know). The brown wire at the fuel cut relay supplies no charge but when supplied a positive charge from the battery it runs the fuel pump continuously. Brown wire goes to fuel pump. It odd that all other wires at this relay have a negative charge? I tried replacing the ecm with a used one to no prevail. Any suggestions to try next?

[Bocephus5781]

Bank angle sensor is working fine. Just tested it.

[Degsy]

Grounds. Those bikes are notorious for bad grounds.

Don't fixate on thr fuel pump. It's a symptom, not a cause. The fuel pump is not priming because the ecu isn't sending the signal to prime because the ecu isn't happy with all the systems. These bugs can be a real bastard to fix, but persevere and you'll get it.

[Paul_E_D]

I've been in IT too long. I read this as not "printing" lol. Did you try rebooting?

[OreoGaborio]

I've been in IT too long. I read this as not "printing" lol. Did you try rebooting?

Four engineers in a car driving down the highway.... A mechanical engineer, an electrical engineer, a thermodynamic engineer & a software engineer.

The car breaks down so they pull to the side of the road.

The mechanical engineers says "The engine didn't sound right right. I think we bent a valve."
The electrical engineer says "No, I think there's something wrong with the ECU or the wiring harness."
The thermo engineer says "No, look at the temp gauge. It's overheating. Something's wrong with the cooling system."
The software engineer says "You guys are a bunch of idiots. Just close all the windows & open em back up again."

[Tokyo Drift]

Trouble shooting per the service manual:

Disconnect FP connector and measure voltage between Brown (+) - Green (-). When you flip the ignition switch to "ON", there should be battery voltage for a few seconds.

If not inspect the following:
-Main fuse 30A
-Sub fuse 10A
-Engine stop switch
There should be continuity between the Black and White/Black terminals with the switch in "RUN"
-Fuel cut-off relay
Remove relay and connect ohmmeter to the Black/White - Brown terminals
Connect 12-V battery to the Brown/Black - Black/White terminals
Continuity should only exist while the battery is connected. If there is no continuity, replace
-Engine stop relay
See Fuel cut-off relay test
-Bank angle sensor
Remove and rotate approx. 60 degrees. Engine stop relay should click and cut power.

Check the Green/Pink wire and Green wire coming off the ECM for continuity to ground.


-EDIT: This came from the 01-03 service manual. 04-07 should be similar.

[scubasteveRR]

Grounds. Those bikes are notorious for bad grounds.

Don't fixate on thr fuel pump. It's a symptom, not a cause. The fuel pump is not priming because the ecu isn't sending the signal to prime because the ecu isn't happy with all the systems. These bugs can be a real bastard to fix, but persevere and you'll get it.

What this man says^^^

I've had an issue like this with my 05 600RR that Degsy helped me diagnose and find.

It was eventually found out to be a short in a Honda repair computer port (which is a ground point for the whole bike) it was a bitch to find.

I know this isn't your issue but this is the diagram picture i made to explain the issue

Yellow_connecor -

[Bocephus5781]

Grounds. Those bikes are notorious for bad grounds.

Don't fixate on thr fuel pump. It's a symptom, not a cause. The fuel pump is not priming because the ecu isn't sending the signal to prime because the ecu isn't happy with all the systems. These bugs can be a real bastard to fix, but persevere and you'll get it.

That is probably the one thing I didn't check. And that would probably make the most sense why it's not working.

[Bocephus5781]

Trouble shooting per the service manual:

Disconnect FP connector and measure voltage between Brown (+) - Green (-). When you flip the ignition switch to "ON", there should be battery voltage for a few seconds.

If not inspect the following:
-Main fuse 30A
-Sub fuse 10A
-Engine stop switch
There should be continuity between the Black and White/Black terminals with the switch in "RUN"
-Fuel cut-off relay
Remove relay and connect ohmmeter to the Black/White - Brown terminals
Connect 12-V battery to the Brown/Black - Black/White terminals
Continuity should only exist while the battery is connected. If there is no continuity, replace
-Engine stop relay
See Fuel cut-off relay test
-Bank angle sensor
Remove and rotate approx. 60 degrees. Engine stop relay should click and cut power.

Check the Green/Pink wire and Green wire coming off the ECM for continuity to ground.


-EDIT: This came from the 01-03 service manual. 04-07 should be similar.

Thanks! This really helps I don't have a service manual so this is valuable information!

[Bocephus5781]

I've been in IT too long. I read this as not "printing" lol. Did you try rebooting?

Yes, I've even disconnected the battery completely to reset the system.