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Fuel pump not priming

7K views 33 replies 9 participants last post by  jdirving 
#1 ·
The bike was running fine. I had it on a lift when I started it up. When switched tanks it stopped priming. The relay is not clicking on the bike, but when I tested the relay off the bike I heard it click. It is reading the right ohms. The bike is not getting fuel but it turns over like it wants to start. I don't have the Fi light on, speedo works, all lights work, and all spark plugs are brand new. It seems like the red kill switch on the handlebars isn't working? I'm finding it very hard to believe that it is the fuel pump because I can't even get a clicking sound. It is not the kickstand switch. I didn't even ride the bike, but just had it running on the lift. Like I said when switched tanks it wouldn't start. Everything is plugged in. I do have the "CHEC" on the speedo. I checked every fuse and they are good. The battery is reading 11.74. How do you check the red killswitch to make sure it is sending power to the relay? Electrical wiring Cable Gas Wire Vehicle
 
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#9 · (Edited)
If the battery is strong enough to turn the bike over it has enough juice to pull in a small relay coil, so chances are its not your battery.

Have you confirmed that you are not getting voltage on the yellow wire with red tracer on the brown connector under the tank before you switch out the relay.

If you are getting voltage on the line side of connector then the relay is working fine.

Then check to see if you are getting voltage on the pump side of the brown connector. If you have voltage on one side and not the other then you know its a problem within the electrical connector.

Before performing this test I would remove the fuel line from the tank, then run a piece of hose from the tank barb into a bucket.
This way you know there is no pressure on the line and the pump should be on the entire time. The pump circuit will open when the pressure cut out is reached.

I am pretty sure if the fuel line is disconnected from the tank with an open hose into a bucket the pump should stay on as long as the key and kill switch are on. But if you do not get voltage you may want to have someone turn the bike over while you check voltage on each side of the connector just to be sure.

If you find you do not have voltage on either side of the connector on the yellow wire with red tracer, then pull a spark plug and confirm you are getting spark. If you are also not getting spark this will lead us to look in a different direction.

A service manual (wiring diagram) and test light will help you greatly to troubleshoot this issue.
 

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#10 ·
If the battery is strong enough to turn the bike over it has enough juice to pull in a small relay coil, so chances are its not your battery.

Have you confirmed that you are not getting voltage on the yellow wire with red tracer on the brown connector under the tank before you switch out the relay.

If you are getting voltage on the line side of connector then the relay is working fine.

Then check to see if you are getting voltage on the pump side of the brown connector. If you have voltage on one side and not the other then you know its a problem within the electrical connector.

Before performing this test I would remove the fuel line from the tank, then run a piece of hose from the tank barb into a bucket.
This way you know there is no pressure on the line and the pump should be on the entire time. The pump circuit will open when the pressure cut out is reached.

I am pretty sure if the fuel line is disconnected from the tank with an open hose into a bucket the pump should stay on as long as the key and kill switch are on. But if you do not get voltage you may want to have someone turn the bike over while you check voltage on each side of the connector just to be sure.

If you find you do not have voltage on either side of the connector on the yellow wire with red tracer, then pull a spark plug and confirm you are getting spark. If you are also not getting spark this will lead us to look in a different direction.

A service manual (wiring diagram) and test light will help you greatly to troubleshoot this issue.
It isn't the battery because I tried it fully charged. I haven't checked the yellow red wire yet, but I'm pretty sure it won't light up when I test it. I still think it is the relay, but it was clicking when I tested it off the bike. The coil part of the relay isn't getting any juice when on the bike. I ordered the relay but I'm still waiting for it to come. I'll figure out something tomorrow after I test the yellow red wire.
 
#12 ·
After testing the yellow wire with red tracer, it isn't getting power just like I figured. I ran a jumper wire from the battery positive straight to the yellow wire with red tracer with brown connector plugged in, and I could hear the fuel pump priming. My question is, could a bad relay stop the yellow wire with the red tracer from seeing power? Anyone have any idea why that wire isn't seeing power? All of the fuses are lighting up with the test light.
 
#13 ·
After testing the yellow wire with red tracer, it isn't getting power just like I figured. I ran a jumper wire from the battery positive straight to the yellow wire with red tracer with brown connector plugged in, and I could hear the fuel pump priming. My question is, could a bad relay stop the yellow wire with the red tracer from seeing power? Anyone have any idea why that wire isn't seeing power? All of the fuses are lighting up with the test light.[/QUOTE

So now check to see if the relay coil circuit is getting voltage when the fuel pump is called.

The yellow wire with black tracer is 12v+ and the orange wire with white tracer is 12v- for the fuel pump relay coil.

Both of the 12v+ and 12v- conductors to the fuel pump relay coil can be opened by the ECU so you have to confirm you have voltage across these two wires.

Did you ever check to see if you are getting spark to your plugs?
The fuel pump relay and and ignition coils share a common 12v- which can also be opened by the ECU as I mentioned above.
If you do not have spark then your problem could the tip over sensor or the ECU can also open this circuit if there is a problem with 2 injector or ignition circuits.
Knowing if you also have spark or not will help you diagnose this problem better.

If you have not already, take a look at the wiring diagram for these circuits and logically deducing the cause of this problem will become clearer for you.
 

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#14 ·
Spark isn't the problem. The fuel pump relay isn't receiving a signal to the yellow red wire. Something is cutting off power to the pump. Right now it seems like it could be the ecu? I have a new fuel pump relay but didn't try it because the old one tested good.
 
#18 · (Edited)
Spark isn't the problem. The fuel pump relay isn't receiving a signal to the yellow red wire. Something is cutting off power to the pump. Right now it seems like it could be the ecu?
I have a pretty good grasp on the situation I assure you and understand fully that your fuel pump relay is not activating.

Have a look at the attachment below and hopefully a light bulb will come on and you will will see how knowing if you also have spark is good troubleshooting information.

This may not end up being your issue but determining if you have spark can either rule it out or help point you in the correct direction.
 

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#17 ·
Just like the kill switch you asked about above, the side stand switch is in series with the starter relay.
You previously said the bike will turn over but will not start, so if that is the case the side stand switch and all other components that are in series with the starter relay coil are working fine and cannot be responsible for the issue you are having.
 

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#16 ·
The kickstand switch has a diode in it, so it won't read 0 ohms when closed. If you hook a meter to it and operate the kickstand switch and the reading varies, the switch is good.

I was having a problem with mine not starting and tried testing the kickstand switch and found this out. Turned out to be the clutch switch, which is just an open/closed switch. Mine would recycle as soon as I hit the starter button, then I noticed if I let the clutch out just a little and hit the button it would start. Took the switch apart and cleaned the contacts and it works fine now. Not much you can do to clean the kickstand switch as the contacts and diode are potted in epoxy. If you want to make sure it's not the kickstand switch, short the two terminals in the connector and see if it works.
 
#26 ·
Still no luck. I even tried another ecu. I can't get a mechanic to come check it out. Some of them won't even return my calls. I guess they hate money? The only thing left is the flasher relay, kickstand switch, tip over sensor, and all of them seem to be working. I can almost guarantee replacing these relays won't help at all. I already replaced the starter relay and the fuel pump relay and it did nothing.
 
#27 · (Edited)
Call the dealer and arrange for them to come and pick up the bike . It would cost you a little bit , but you would finally solve the problem whatever it is once they hook the bike to their computer and see what is causing it .
After all your tries and realizing that nothing have worked , that is what I would do .
 
#33 ·
jd, before you take it in, I would check that clutch switch. That's the only switch on mine that has actually failed. When it was going bad, I could get it to prime/start by slowly letting the clutch out while holding the starter button in. It would hit a point where the switch would make contact and it would fire up. I bought a new one, but before I got it I took the old switch apart and cleaned the contacts and it worked fine. It's just a simple sliding switch, and it's easy to remove and disassemble to clean. Once the screw or screws are removed that hold the switch on, the case just pulls apart.

The same thing can happen if the pin on the switch isn't making contact with the clutch lever. You can see if it is or not by looking under the clutch lever and noting where the pin is. It's easy to get the pin out of place when installing the switch or replacing the clutch lever.
 
#34 ·
It isn't the clutch switch. It has been checked by 3 different people. I got the F1 light to come on and got C41. The F1 light is off now and isn't coming back. The only thing left is the ecm and kill switch. The mechanic said the kill switch tested good, but I still might try another one. The relay looked bad, but I cleaned the connector and tried another one and it didn't help. It isn't the brown connector under the tank because it isn't getting any power. I saw on another forum where someone said they took their ecm to the dealer and they said it tested good, but he tried another anyways and it worked. He had the no priming issue.
 
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