Could you be a little clearer pleaseYou're going in the wrong direction trying to find the fault.
You're swimming from a long way upstream with lots of diversions along the way to the fault.
Start at the fault and work back downstream.
fuel pump help
- Thread starter spen
- Start date
How clear ? As posted.
Start at the fault and work back. Don't start at the fuse box and work towards the fault.
And you need to be a little clearer. What do have in the way of test equipment for a start.
I started at the fault no noise of pump priming,tested the fuse,tested the relay, tested the pump , all of these are ok ,tested the power coming into and out of the fuse box all ok then tested the wire carrying the power up to the pump and found no conductivity,i then ran a piggy back wire from the start of the green and white at the fuse box from the relay up to the block connector at the tank ,turned the ignition on and bingo the pump primes ,hit the button and the bike runs !!i have muli meter and a bulb with wires to test with ,do you think running the bike with this piggy back wire will do any harm ??by coming straight off the relay to the tank connector have i bypassed anything of importance ?
Your break sounds like it is between the tank connector and the solder joint where all the green/white wires connect.
There is nothing wrong with what you have done and provided you have used the correct current rated wire ( or better ) should be 1mm minimum. Then every thing should work.
There is an old trick you can use if you need to chase a break in a wire, and that is to use a dress makers pin and push it all the way through the outer insulation until it makes contact with the conducting wire. When you pull the pin out the insulation should spring back to seal the wire.
There is nothing wrong with what you have done and provided you have used the correct current rated wire ( or better ) should be 1mm minimum. Then every thing should work.
There is an old trick you can use if you need to chase a break in a wire, and that is to use a dress makers pin and push it all the way through the outer insulation until it makes contact with the conducting wire. When you pull the pin out the insulation should spring back to seal the wire.
Thank you i used a heavier wire and a 10amp inline fuse ,all seems good
thanks for your straight answer
Mark Like I said yesterday it will let the bike run "But" you may be masking something else
You need a bulb tester I would say it's better to unlink your wire and test @ the pump connection for volts if none then trace the fuel pump connector block wiring back until you do get a lit lamp
You can bridge the fuel pump relay "load" circuit contacts with a couple of male spades and one of your inline fuse holders With maybe a 2 or 3 amp fuse you just need volts not current and as suggested previously use a needle and just penetrate the wire and connect thru a bulb to a decent frame earth
If it lights it's not broken move on back to the next turn or obstacle that might cause a break
IF you don;t find a break then roll up your bridge wire and keep it tucked up in the fuse box or wherever "just in case" it happens again
It may have been something simple it may have been the ECU decided not to stir up the pump (can't have been a fuel pump controller ;-) cos they don;t have one)
At least this way you eliminate a broken fuel pump feed and have a back up plan just in case (bridge wire in fuse box that you know works)
You need a bulb tester I would say it's better to unlink your wire and test @ the pump connection for volts if none then trace the fuel pump connector block wiring back until you do get a lit lamp
You can bridge the fuel pump relay "load" circuit contacts with a couple of male spades and one of your inline fuse holders With maybe a 2 or 3 amp fuse you just need volts not current and as suggested previously use a needle and just penetrate the wire and connect thru a bulb to a decent frame earth
If it lights it's not broken move on back to the next turn or obstacle that might cause a break
IF you don;t find a break then roll up your bridge wire and keep it tucked up in the fuse box or wherever "just in case" it happens again
It may have been something simple it may have been the ECU decided not to stir up the pump (can't have been a fuel pump controller ;-) cos they don;t have one)
At least this way you eliminate a broken fuel pump feed and have a back up plan just in case (bridge wire in fuse box that you know works)
It may have been something simple it may have been the ECU decided not to stir up the pump (can't have been a fuel pump controller ;-) cos they don;t have one)
During testing the ECU must be sending a signal to prime the pump because as i checked the relay and turned the ignition on i got a reading at the relay on the live feed out for around two seconds ,i assume this is the ECU sending power to prime the pump .
During testing the ECU must be sending a signal to prime the pump because as i checked the relay and turned the ignition on i got a reading at the relay on the live feed out for around two seconds ,i assume this is the ECU sending power to prime the pump .
It completes the the fuel pump relay switching circuit to activate it for the 2 seconds
It does this when the ignition circuit is energised by :- Ign switch, Kill switch, Sidestand being lifted while clutch pulled and in gear, etc etc it is a default setting
once running it grounds the relay swicthed circuit again to complete the circuit and keep the fuel coming
Don't try and overcomplicate this.
The motronic is doing exactly what it is designed to do. You have found the problem. Open circuit from the fuel pump relay to the fuel pump connector. If you had any more than that, then the bike would not run when you fitted your bypass because the same feed from your relay goes to the injectors, and they are working fine.
The break is between the solder connection (actually a crimp) to the fuel pump tank connector. I doubt the wire has chaffed through as that would likely have blow the fuse, and your bike would not run. Therefore my money is either on a failure at the crimp end, or more likely a failure probably through corrosion at the pump tank connector. I doubt the break is anywhere else unless your wiring loom is flexing somewhere along it's route, or this stretch of wiring has degraded due to over current ( getting hot ), or it was poor quality at manufacture.
The motronic is doing exactly what it is designed to do. You have found the problem. Open circuit from the fuel pump relay to the fuel pump connector. If you had any more than that, then the bike would not run when you fitted your bypass because the same feed from your relay goes to the injectors, and they are working fine.
The break is between the solder connection (actually a crimp) to the fuel pump tank connector. I doubt the wire has chaffed through as that would likely have blow the fuse, and your bike would not run. Therefore my money is either on a failure at the crimp end, or more likely a failure probably through corrosion at the pump tank connector. I doubt the break is anywhere else unless your wiring loom is flexing somewhere along it's route, or this stretch of wiring has degraded due to over current ( getting hot ), or it was poor quality at manufacture.
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Bit of info.
The green/white wire (1.5mm) comes from the fuel pump relay travels 96 cm along the loom to a crimp connection. (left hand side of bike) two green/white wires (0.75mm) run to each injector, and another green/white wire (0.75mm) runs to the timing valve, this timing valve is only fitted to US models, but the connector is on the right hand side of the frame just to the rear of the fuse box.
The other green/white wire (1.0mm) runs from the crimp connector for 62 cm through the loom to the tank connector.
This is the length of wire your fault is on.
The green/white wire (1.5mm) comes from the fuel pump relay travels 96 cm along the loom to a crimp connection. (left hand side of bike) two green/white wires (0.75mm) run to each injector, and another green/white wire (0.75mm) runs to the timing valve, this timing valve is only fitted to US models, but the connector is on the right hand side of the frame just to the rear of the fuse box.
The other green/white wire (1.0mm) runs from the crimp connector for 62 cm through the loom to the tank connector.
This is the length of wire your fault is on.
There is only one crimp. It's how they build the looms, they work back from the connectors, gather all the wires of the same colour together trim to length and fit a crimp.
So if the crimp is on the left hand side of the bike in the loom next to the alternator. Then from there the wires run to the fuel pump relay, injector left, injector right, timing valve, fuel pump connector and I forgot, the lambda connector.
Hope this makes sense.
So if the crimp is on the left hand side of the bike in the loom next to the alternator. Then from there the wires run to the fuel pump relay, injector left, injector right, timing valve, fuel pump connector and I forgot, the lambda connector.
Hope this makes sense.
As has already been suggested. Start at the fuel pump connector, and work your way back to the crimp. You may find the break is close to the connector.
Getting to the crimp involves tank removal and lot of unravelling of tape. But if you do choose to go there. When you look at the loom, you will see a thick black taped stub about 6 to 9 inches long folded back onto the loom. All the crimped tails are in this stub.
Getting to the crimp involves tank removal and lot of unravelling of tape. But if you do choose to go there. When you look at the loom, you will see a thick black taped stub about 6 to 9 inches long folded back onto the loom. All the crimped tails are in this stub.
Perfect sensethanks for your time
The break can only be from the crimp to your tank connector. If it was between the crimp and your relay, then your injectors would not work.
Personally, I would work back from the connector, pushing a dress makers pin through the wire, and test every 6 inches. However, from the connector the loom disappears under the battery tray, so the difficulty of access kind of balance out.
It would help if you did as Jay says to bridge the fuel pump relay so you have power on the line continuously for checking, rather than having to switch on and off all the time to get the 2 seconds. Just disconnect the fuel pump to stop it running continuously.
It would help if you did as Jay says to bridge the fuel pump relay so you have power on the line continuously for checking, rather than having to switch on and off all the time to get the 2 seconds. Just disconnect the fuel pump to stop it running continuously.
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