So I did a bunch of testing including hooking the fuel pump up directly to the battery and it cycles just fine. Testing the wiring showed there is no problem. However when I hook the fuel pump electrical line to its harness it doesn't work even though my tester shows good voltage at that plug in. I had started the day thinking my fuel pump was faulty so I had all that apart, cleaned it all put it back together when it tested just fine. My battery was down a bit. Could it be down enough that the fuel pump won't cycle unless direct connected to the battery? Or should I just replace the wiring connection? Welcome any suggestions or insights!
Fuel pump won't cycle...
- Thread starter CRidesAgain
- Start date
I was thinking maybe it was a fuel pump relay but apparently the 2010 nt700v does not have such a thing.
When I got to about 120K on my first NT, it started having a problem with running smoothly and with normal power when I opened the throttle more than about 2/3 of the way. It would start running like a carbureted bike with the choke applied. I'm past the point of doing any maintenance on my bike so I took it to the shop. I told the tech that I was willing to bet it was a fuel pump that needed replacement. He said that that was the most expensive thing it could be and asked if I was in any hurry. I wasn't in too much of a rush because the weather had started getting cold. He told me that if I could leave it with him, he'd mess with it when he wasn't tied up with other jobs. I don't know what all he tried, but I do know that he had it on their dyno at least a couple of times and that he never got it fixed. Finally, he pulled the fuel pump and flow tested it. Pressure was good, but the flow was about 20% of what it should have been. We replaced the fuel pump and the bike was still running great when I traded it in on my 2nd NT.
But your symptoms don't sound at all like mine. Some on the Forum will be able to help you; about all I can do is offer encouragement.
Where in rainy western Oregon do you live? I've ridden quite a few miles in Oregon, all across the state since I started riding in '98. One ex-member of our forum who can't ride now due to age and serious vision issues lives in Woodburn and I visited him back in '17 on my way Abbotsford, BC, to start the SCMA Three-Flags Ride.
Tell us a bit more about yourself and your riding history, why doncha'? I've been riding since '97; bought my first bike, an '83 Honda GL650i Silverwing in February of '98 and next came two '99 Kawasaki Concours. I wrecked the first one in '06 after 115K miles. I bought its near twin about three months later and rode it 50K miles before trading it in for my first '10 NT700VA in March of '10. By then I'd had five knee replacements and the Concours was just too heavy. I'd seen and sat on an '08 NT700V Deauville in Mannheim, Germany in the summer of '08 and was impressed with it.
I rode that bike 139K miles before trading it in on its near twin in July of '20. #1 was SN00079; #2 is SN00063, but only had 22K when I bought it. This is #2:
But your symptoms don't sound at all like mine. Some on the Forum will be able to help you; about all I can do is offer encouragement.
Where in rainy western Oregon do you live? I've ridden quite a few miles in Oregon, all across the state since I started riding in '98. One ex-member of our forum who can't ride now due to age and serious vision issues lives in Woodburn and I visited him back in '17 on my way Abbotsford, BC, to start the SCMA Three-Flags Ride.
Tell us a bit more about yourself and your riding history, why doncha'? I've been riding since '97; bought my first bike, an '83 Honda GL650i Silverwing in February of '98 and next came two '99 Kawasaki Concours. I wrecked the first one in '06 after 115K miles. I bought its near twin about three months later and rode it 50K miles before trading it in for my first '10 NT700VA in March of '10. By then I'd had five knee replacements and the Concours was just too heavy. I'd seen and sat on an '08 NT700V Deauville in Mannheim, Germany in the summer of '08 and was impressed with it.
I rode that bike 139K miles before trading it in on its near twin in July of '20. #1 was SN00079; #2 is SN00063, but only had 22K when I bought it. This is #2:
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- 2010 NT700V
You desperately need to get yourself a wiring schematic. The + path for the fuel pump passes through the switched side of two relays before it gets to the fuel pump. The engine cut-off relay first, then the fuel cut-off relay.
You mentioned your battery was low, start there. Hook up a good battery with a tested capacity. The fuel pump isn't the only load when you key on the bike requesting juice from the battery. There's lights, including the 70 watt headlight bulbs.
When I got to about 120K on my first NT, it started having a problem with running smoothly and with normal power when I opened the throttle more than about 2/3 of the way. It would start running like a carbureted bike with the choke applied. I'm past the point of doing any maintenance on my bike so I took it to the shop. I told the tech that I was willing to bet it was a fuel pump that needed replacement. He said that that was the most expensive thing it could be and asked if I was in any hurry. I wasn't in too much of a rush because the weather had started getting cold. He told me that if I could leave it with him, he'd mess with it when he wasn't tied up with other jobs. I don't know what all he tried, but I do know that he had it on their dyno at least a couple of times and that he never got it fixed. Finally, he pulled the fuel pump and flow tested it. Pressure was good, but the flow was about 20% of what it should have been. We replaced the fuel pump and the bike was still running great when I traded it in on my 2nd NT.
But your symptoms don't sound at all like mine. Some on the Forum will be able to help you; about all I can do is offer encouragement.
Where in rainy western Oregon do you live? I've ridden quite a few miles in Oregon, all across the state since I started riding in '98. One ex-member of our forum who can't ride now due to age and serious vision issues lives in Woodburn and I visited him back in '17 on my way Abbotsford, BC, to start the SCMA Three-Flags Ride.
Tell us a bit more about yourself and your riding history, why doncha'? I've been riding since '97; bought my first bike, an '83 Honda GL650i Silverwing in February of '98 and next came two '99 Kawasaki Concours. I wrecked the first one in '06 after 115K miles. I bought its near twin about three months later and rode it 50K miles before trading it in for my first '10 NT700VA in March of '10. By then I'd had five knee replacements and the Concours was just too heavy. I'd seen and sat on an '08 NT700V Deauville in Mannheim, Germany in the summer of '08 and was impressed with it.
I rode that bike 139K miles before trading it in on its near twin in July of '20. #1 was SN00079; #2 is SN00063, but only had 22K when I bought it. This is #2:
Hi Phil! Wow love that bike and your history! More later, have to get ready for work. Here is a photo of my 1985 silverwing 500. Loved that bike!When I got to about 120K on my first NT, it started having a problem with running smoothly and with normal power when I opened the throttle more than about 2/3 of the way. It would start running like a carbureted bike with the choke applied. I'm past the point of doing any maintenance on my bike so I took it to the shop. I told the tech that I was willing to bet it was a fuel pump that needed replacement. He said that that was the most expensive thing it could be and asked if I was in any hurry. I wasn't in too much of a rush because the weather had started getting cold. He told me that if I could leave it with him, he'd mess with it when he wasn't tied up with other jobs. I don't know what all he tried, but I do know that he had it on their dyno at least a couple of times and that he never got it fixed. Finally, he pulled the fuel pump and flow tested it. Pressure was good, but the flow was about 20% of what it should have been. We replaced the fuel pump and the bike was still running great when I traded it in on my 2nd NT.
But your symptoms don't sound at all like mine. Some on the Forum will be able to help you; about all I can do is offer encouragement.
Where in rainy western Oregon do you live? I've ridden quite a few miles in Oregon, all across the state since I started riding in '98. One ex-member of our forum who can't ride now due to age and serious vision issues lives in Woodburn and I visited him back in '17 on my way Abbotsford, BC, to start the SCMA Three-Flags Ride.
Tell us a bit more about yourself and your riding history, why doncha'? I've been riding since '97; bought my first bike, an '83 Honda GL650i Silverwing in February of '98 and next came two '99 Kawasaki Concours. I wrecked the first one in '06 after 115K miles. I bought its near twin about three months later and rode it 50K miles before trading it in for my first '10 NT700VA in March of '10. By then I'd had five knee replacements and the Concours was just too heavy. I'd seen and sat on an '08 NT700V Deauville in Mannheim, Germany in the summer of '08 and was impressed with it.
I rode that bike 139K miles before trading it in on its near twin in July of '20. #1 was SN00079; #2 is SN00063, but only had 22K when I bought it. This is #2:
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I want to thank you for sending me the picture of your Silverwing 500. It wasn't an '85, though. Silverwing production (at least motorcycle Silverwing production) stopped after '83. The Silverwing 500 was built in '81 and '82. The 650 was only built in '83. Somehow I've ended up with not a single decent picture of my '83. Your picture looks a lot like my bike. The biggest visual difference (except for displacement and different-looking cylinder heads) was that mine had a Markland conversion that let you keep the topbox on the bike and still have the pillion seat available. It also had engine protection and luggage protection bars that came from Markland. Plus mine had the biggest windscreen ever made for the 81-83 Goldwings.
Gosh darn it Phil you are right.. I spaced on the year it was a 1981! The 650 sounds great, I liked the look my 500 had but always had to choose between my wife riding on the back or having the top box!
I moved on to a V-Strom 650 after that which was a nice bike to commute with for a few years but not as much character! Now I just have the NT 700,
Which is a great all-around commuter, last year I was looking for just a really reliable all -arounder and noticed this one for sale down in coos Bay. The guy wanted 2800 for it but it had a rebuilt title because the older gentleman first owner had 'dropped it in the driveway'. He agreed to take $2,500 for it and I wrote it back up to Newport where we live! well it turns out the damage was a little more extensive than a drop in the driveway of course, but nothing too bad and it has still been a good friend. I never put near as many miles on bikes as it sounds like you do as I'm a fair weather Rider and we get 9 months of cold rain it feels like around here!
I think I've got my problem figured it seems like it's going to be where the fuel pump electrical sub harness connects to the main harness that connection looks really crummy. I'm going to splice a brand new 3-wire connection right there and hope it will work.. if not process of elimination.. sounds like the next step would be to try a new fuel pump just in case this one is wearing out or at least get it tested and see the output.
You mentioned that the pump worked when you applied power directly to it. When you did that, you took a few things out of the circuit...the kill switch, the sidestand switch, which cuts the pump power when the stand is down and the bike is in gear, the tip over sensor, and the pump relay if it has one.
Good luck.
Good luck.
Coyote Chris
Site Supporter
If a fuel pump is showing its definately getting voltage and it works off the bike but not on, my first question is, Where is the voltmeter ground? Where is the fuel pump ground? If there is positive voltage at the connector and that connector is good, then stick a sharp probe on to the positive lead of the voltmeter and measure the voltage at the negative wire that goes to the pump. With respect to bike frame ground. I dont have the schematic and I am assuming there is a ground wire for the fuel pump. It should be zero but a better test is if that wire SHOULD go to bike ground, take a piece of wire and attach it to bike ground and then to the connector ground wire
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- 2010 NT700V
The Haynes service manual for the NT is $25 - $35 and includes a full color wiring schematic that is easier to read than the Honda one.
FYI for those that aren't familiar with bike electrics, Honda (and probably most brands) has used a fuel cut-off relay for the pump ever since they started putting on fuel pumps in the 1980's. Perhaps even earlier, but I don't recall fuel pumps on the 1970's CB series.
FYI for those that aren't familiar with bike electrics, Honda (and probably most brands) has used a fuel cut-off relay for the pump ever since they started putting on fuel pumps in the 1980's. Perhaps even earlier, but I don't recall fuel pumps on the 1970's CB series.
The fuel pump relay on carburetors with electric fuel pumps was a safety measure. The relay only got power when the engine was running. The bikes without an electric pump, usually used a vacuum line to shut the fuel off. The tip over sensor pretty much does the same thing on a FI bike, although it may use a relay to power the fuel pump.
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- 2010 NT700V
All significant inductive loads (motors) on any vehicle are going to be powered through a relay. A bike may have a tip over sensor, but that doesn't negate the use of a relay for the fuel pump. The tip over sensor is simply going to instruct the logic circuit to open the relay contacts for the pump.
All the big inductive loads on the NT are through relays. The radiator fan, fuel pump, and starter motor all have their current path open and closed with the use of relays.
If you were to upgrade the horn on the NT to something like a Stebel Nautilus you would add a relay. Simply plugging up the horn wires as is would blow a fuse, or worse fry the wiring. Instead, you would move the bike's horn wires over to the coil side of a new relay. A new run of appropriate gauge wire would then be ran from battery +, through a new fuse holder with proper size fuse, into a contact on the switched side of a relay, out the switched side of the relay to the Stebel Nautilus, then Nautilus to Ground. The horn switch is still working, but is now isolated from the current draw of the larger horn. It is now solely energizing the relay coil.
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Good info. Thanks.
There is a Fuel Pump Relay, see the circled section of the wiring diagram below.
The relay is controlled by the ECU. There are several logic conditions that must be met before the pump relay will cycle when the bike is powered up. The most important one is that the kill switch needs to be in the run position. Then it should power up for several seconds to pressurize the fuel rail. Then there’s a list of items to check on if it doesn’t in the service manual, the bank sensor is one of those items listed.
The relay is controlled by the ECU. There are several logic conditions that must be met before the pump relay will cycle when the bike is powered up. The most important one is that the kill switch needs to be in the run position. Then it should power up for several seconds to pressurize the fuel rail. Then there’s a list of items to check on if it doesn’t in the service manual, the bank sensor is one of those items listed.
If you had battery voltage at the connecter to the fuel pump that means all the logic has been met to run the fuel pump. That's good news because it eliminates the Fuel Pump Relay and it's contact, any ECU logic to turn on the fuel pump relay, FI/IGNITION relay and it's contact, BANK ANGLE SENSOR, ENGINE STOP SWITCH, IGNITION SWITCH, fuses, and wiring to the battery... all has to be good. Everything to the left of the Fuel Pump in the attached pic should be good... except the battery could be too low to carry all the lights + the fuel pump. Charge the battery or jump the battery to a vehicle battery first.
Since the fuel pump runs when connected directly to 12V... it should be good. What else might be bad? The ground wiring from the fuel pump to ground, or the FUEL PUMP connector itself. When you check the voltage at the fuel pump read directly from both connectors (one lead on one wire to the fuel pump, the other wire on the other wire from the fuel pump). There should be 12V across the two connectors with Ignition switch and engine stop switch on for a normal start. If you get 0V across the fuel pump connectors, but are getting 12V from one wire to chassis ground, then the ground wire from the fuel pump to ground is open.
Noticed on the wiring diagram Brillot2000 posted that the FUEL UNIT sensor (fuel gauge) shares the ground wire (Bl/W wire then G after the 3 pin connector) with the fuel pump. That makes a handy way to verify the shared ground wiring with the fuel pump and fuel unit sensor is good. Simply verify if your fuel gauge is working when you turn the ignition on. If it's not working your Fuel Pump problem is most likely going to be the same ground wiring that prevents the fuel gauge from working.
Since the fuel pump runs when connected directly to 12V... it should be good. What else might be bad? The ground wiring from the fuel pump to ground, or the FUEL PUMP connector itself. When you check the voltage at the fuel pump read directly from both connectors (one lead on one wire to the fuel pump, the other wire on the other wire from the fuel pump). There should be 12V across the two connectors with Ignition switch and engine stop switch on for a normal start. If you get 0V across the fuel pump connectors, but are getting 12V from one wire to chassis ground, then the ground wire from the fuel pump to ground is open.
Noticed on the wiring diagram Brillot2000 posted that the FUEL UNIT sensor (fuel gauge) shares the ground wire (Bl/W wire then G after the 3 pin connector) with the fuel pump. That makes a handy way to verify the shared ground wiring with the fuel pump and fuel unit sensor is good. Simply verify if your fuel gauge is working when you turn the ignition on. If it's not working your Fuel Pump problem is most likely going to be the same ground wiring that prevents the fuel gauge from working.
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To check the relay's proper operation, you can insert a short length of wire between the line in (12v) connector on the relay to the line out connection to the fuel pump then switch on the ignition. If that runs the fuel pump, then it is the relay that is faulty, or the 'trip' lines that enter the relay on the two other terminals to close the relay have some fault.
Not sure this has been clearly explained so I thought I would add my thoughts.
In nearly all fuel injected vehicles, and I believe the NT700 is one of these, the fuel pump does NOT run all the time that the ignition is turned on.
The fuel pump turns on when the ignition is switched on and then turns OFF after a few seconds. The fuel pump does not turn on again until the ECU instructs it to. This is typically when the ECU senses a signal from the crankshaft and/or camshaft sensors. The signal from these sensors confirms the engine is running.
The reason I am advising of this is to advise that you should NOT expect 12 volts at the fuel pump connector all the time as it is only present when the ECU allows it to be.
To add another complexity, in some vehicles the ECU actually switches the ground/earth wire. I am not certain if this is the case with the NT700 but if it is, you actually WILL measure 12 volts at the fuel pump connector all the time but the ground/earth will be missing. You can therefore simply connect the fuel pump ground/earth wire to the battery negative terminal and the fuel pump should run any time the key is switched on and the kill switch is not on (and the tip over sensor is not active).
Hope this helps.
Seagrass
In nearly all fuel injected vehicles, and I believe the NT700 is one of these, the fuel pump does NOT run all the time that the ignition is turned on.
The fuel pump turns on when the ignition is switched on and then turns OFF after a few seconds. The fuel pump does not turn on again until the ECU instructs it to. This is typically when the ECU senses a signal from the crankshaft and/or camshaft sensors. The signal from these sensors confirms the engine is running.
The reason I am advising of this is to advise that you should NOT expect 12 volts at the fuel pump connector all the time as it is only present when the ECU allows it to be.
To add another complexity, in some vehicles the ECU actually switches the ground/earth wire. I am not certain if this is the case with the NT700 but if it is, you actually WILL measure 12 volts at the fuel pump connector all the time but the ground/earth will be missing. You can therefore simply connect the fuel pump ground/earth wire to the battery negative terminal and the fuel pump should run any time the key is switched on and the kill switch is not on (and the tip over sensor is not active).
Hope this helps.
Seagrass
Let me bring into the light that the ECU provides an "Active Low" signal (0-Volts) to turn on the "Fuel Pump Relay". One side of the relay is at a constant 12 Volts. The ECU must supply a "0-Volt" signal in order to activate the relay and in turn the fuel pump.Noticed on the wiring diagram Brillot2000 posted that the FUEL UNIT sensor (fuel gauge) shares the ground wire (Bl/W wire then G after the 3 pin connector) with the fuel pump. That makes a handy way to verify the shared ground wiring with the fuel pump and fuel unit sensor is good. Simply verify if your fuel gauge is working when you turn the ignition on. If it's not working your Fuel Pump problem is most likely going to be the same ground wiring that prevents the fuel gauge from working.
Hope this explanation of operation helps with better defining the conditions that must occur. The Brown/Blue wire will be the signal from the ECU to the Fuel Pump Relay. With the relay in place, the voltage at the Brown/Blue will be 12-volts referenced from the chassis ground until the ECU sends the activation signal of 0-Volts.
For 12VDC to get to the Fuel Pump connector the Fuel Pump Relay and the FI/Ignition Relay have to be working. If either relay coil or it's contact fail the connector would never get 12vdc. Maybe the connector isn't getting fully plugged into the Fuel Pump.
Agreed. The ECU has to ground (err "Active Low" or "0-Volt" signal... same thing, I think) that side of the Fuel Pump Relay to complete the circuit. Again though, CRidesagain said that he was seeing 12VDC at the Fuel Pump, implying that the Fuel Pump Relay had to be working, implying that the ECU had to be working to complete the circuit to the Fuel Pump Relay.
Coyote Chris
Site Supporter
Good info about the "active low" or "switched ground" FP operation from you guys. Yes, the fuel pump doesnt work constantly until the motor turns.