Jump to content

Honda Experts


Mister2

Recommended Posts

i have a 2000 CBR 600 f4...it quit running for me a few days ago...i worked on it a bit and found out my fuel pump was not delivering fuel...but if i jumper the harness the pump clicks and continues until the carbs are filled then it stops and bike runs fine until carbs go empty again...when i turn key on i get 12v at the pump for a brief sec. then no power...my question is what tells the pump to turn on and off? because this is what i think is wrong b/c i ran a jumper harness to the fuel pump constant 12v and the bike runs fine....any suggestions??? thanks for any info...much appreciated

Link to comment
Share on other sites

If jumper starts the fuel pump, it should be one (or more) of these items not working:

Or the wiring between any of them...

(from the 2004 CBR600RR manual)

(1) Engine stop relay

(2) PGM-FI fuse (20A)

(3) Engine stop switch

(4) Sub fuse (10A)

(5) Ignition switch

(6) Main fuse A (30A)

(7) Bank angle sensor

(23) Fuel cutoff relay

The current path to the fuel pump is battery-(2)-(1)-(23)-fuel pump-ground

The engine stop relay is activated by battery-(6)-(5)-(4)-(3)-(1)-(7)-ground

Bank angle sensor is powered by a connection to (4) Sub fuse (10A)

edit: Should be able to narrow it down quickly by using a Volt-Ohm-Meter.

edit 2: It's probably just one of the three fuses...

Edited by ReconRat
Link to comment
Share on other sites

well its carbed though....so i dont think i have half thoes sensors...also it is running fine now....i think my fuel pump is just getting weak (ive heard that the pump on CBR's have a lot of issues)

i checked again and i am getting battery voltage to the pump maybe i didnt have a good connection w/ my meter before...but i put new fuel filter on and put my mouth on the line and pushed fuel thru until i could hear it going into the carbs...but my guess is that its just getting weak??

Link to comment
Share on other sites

Maybe it didn't have voltage to the fuel pump before.

Fuel injection or carb with computer, both will have a lot of sensors and switches.

I'll have to back up and try to find an older CBR600 manual.

Link to comment
Share on other sites

Much more complicated...

ok, power to the fuel pump appears to be on all the time. Except, the power from the ignition switch, runs through a fuel pump transfer relay, and then through a fuel cutoff relay, and then through the solenoid relay(air vent), and then to something else up around ignition and handlebars to ground it, I think... this wiring diagram is much harder to read. The diagnostics for fuel pump is an eight page set of voltage checks.

The fuel pump transfer relay activates the fuel pump. The fuel pump transfer relay, fuel cutoff relay, and solenoid relay(air vent) should be on the right side of the tail under the seat. There's four or five relays there, I think, but I don't know what the others are yet. The air vent solenoid is under the tank. I don't see a tip/tilt cutoff switch.

You should also hear a click/pop when you turn the key on, that's the air vent solenoid working. The ECM unit also is sending a signal to the fuel cutoff relay. That would be the rev limiter. fuel cutoff relay also appears to kill power to one plug coil when it cuts off fuel.

This also assumes it's not one of the eleven other fuel related reasons a bike will crank and not start. Most are basic things you've already checked.

oops, here's the shop manual:

http://www.stephygee.com/F4manual.zip

from this website:

http://www.stephygee.com/

I had to download it twice, the first download was corrupted...

edit: there is also a procedure to check the fuel pump output flow capacity. It should pump 23.7 US ozs per minute.

Edited by ReconRat
Link to comment
Share on other sites

  • 4 years later...

brining this one back from the way dead.. i replaced the fuel pump back then and it fixed it...Until now, its doing the same thing again. ive confirmed that when i key on the fuel pump does not prime, i ran overlay power wire to prime it, fired right up, i put the stock wiring back in place and hooked up my meter with it running im getting voltage at the pump and its running great.. so it seems its just not wanting to do the initial prime. i went though the Service manual flow chart, it wants me to put the rear wheel up and get above 18 mph and check voltage, but i do not have the means to do that, anyone have issues like this? ive googled and done tons of searching, but cant really find any info.

Link to comment
Share on other sites

You could rig up a volt meter where it can be watched, and ride the bike. Over the years I've gotten the impression that 600 fuel pumps and/or fuel pump circuits are prone to failure. Not sure exactly what it is that causes it. Mostly seem to hear the exact same thing. Replaced the fuel pump and it happened again.

 

Best guess. By running a jumper to the fuel pump, the circuit was improved. Better voltage, amps, etc. Somewhere in that wiring to turn on and prime the fuel pump, there is a voltage drop. Even a corroded connector could cause that.

 

edit: And yes, it could be the fuel pump again...

Edited by ReconRat
Link to comment
Share on other sites

You don't need to go 18 mph. They are getting you to a certain RPM....many bike charging systems don't put out much at idle. Do it by ear, rev it in neutral so it sounds like the revs at 18.

But you don't have a charging system problem unless you battery is going dead on you.

Link to comment
Share on other sites

https://answers.yahoo.com/question/index?qid=20110412224212AA7mnaz

I found this..it may or may not be of help. First thing I would do is check battery voltage....key off....key on. If it is low,charge the battery and see what happens. Always start diagnosing with a fully charged battery. Sometimes when chasing electrical issues it is advantageous to back track...meaning starting at the pump and tracing back to the voltage source. Being 15 years old corroded connections could be a possibility. Check all that you can and address as needed. I also found a schematic on line and it seems as though the fuel cut off relay gets a signal from the #1 coil. It is possible that this is what tells the relay to close and run the pump when the engine is cranking/running. There is a connection showing in that circuit that you should check. You can also do a bypass on the bank angle sensor to rule it out. It could be a low voltage thing being Honda...if while cranking my Wing and the voltage drops below 10.5 volts it will not start...will crank but not start. Just some thoughts...a shot in the dark as it were. Also by hot wiring the fuel pump you are basically bypassing what ever is the issue in the circuit.

Edited by Al Z. Heimer
Link to comment
Share on other sites

Thanks for the help guys, i replaced the battery because it is old and not wanting to hold a charge after winter. i also put a new fuel pump in because, well thats what fixed it last time. i also verified the charging system is working, 14v, but at the fuel pump im only getting around 9v, so seems like a hefty voltage drop. i continued on the flow chart and the last step i landed on was to check power on pink/yellow wire with key on engine off and there should not be voltage, but i am getting voltage, so it says to replace the fuel pump transfer relay. but i can hear it click on when i key on, but i plan to order a new one this week and see what happens. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...