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Discussion Starter #1
I have been searching and searching and cannot find anything on this specific issue. Yes, another fuel pump priming issue but here is what I have:

No power from ECU to fuel pump relay
BAS has been bypassed
Kill switch works
Relays all work
Fuel pump works - via adding power by secondary source (powerprobe)
Key has proper output

I am not sure what else to check. This is a buddies bike that he dropped in a corner and it hasnt been right since. I am going to pull the panels off to double check for any cut wires but I am not finding anything so far. Thoughts? I am assuming the ECU might be bad but I do not know how to tell if that is the case.
 

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Bad ECU. If you can bypass the relay and turn on the fuel pump then the sender from the ECU is bad. Swap it with a good one and you should be fine.
 

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Discussion Starter #4
ECU didnt work. I still have no power to the fuel pump relay with a new ECU. I guess I need to trace each wire to see what is going on.
 

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Pull off your left fairing and pull the connectors for the harness apart and make sure the pins are all making connection. Can't remember if its the blue connector or gray. Check both.

Sent from Motorcycle.com Free App
 

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The ECU sends a ground to the fuel pump relay. If everything is connected and you send a ground to that relay does it work?

What year bike?
 

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Discussion Starter #7
It is a 2008. I will try getting a ground to it this evening as I'm not at home. It was laid down on the left side in a slow crash but the body work is a bit torn up so it could be a broken connection down there. I didnt see anything wrong in my first pass through everything.
 

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Also check your ground lug. It will have all your ground connections in one clump.
 

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Discussion Starter #9
Where is the ground lug located? I know its on the frame but a general location would be good to make it easier to find.
 

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I think it is behind the right mid fairing.
 

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Discussion Starter #11
When I unplug the wiring on the left side of the bike I get power to the fuel pump relay. I must have a short somewhere. Fuel pump still didn't turn on though
 

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Still have clutch/kickstand safeties attached?
 

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Discussion Starter #13
The kickstand wiring is still attached.

When I disconnect the connectors on the left hand side of the bike (1 gray, 2 white, 1 black, and one green) I don't get any power to the relay. I plugged everything back in.

When I removed the ground bolt and wires from the frame I immediately got .75v at the relay. I then removed the green plug and the relay received 12.75 volts and the headlights shut off.
 

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I would do the plugs one by one and see which one is changing the relay. You bypassed the bas correctly? Outside wires are shorted together, middle one cut not used.
 

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Discussion Starter #15
The green plug is changing the relay provided the ground is removed as well. If the ground is still connected the relay only goes to .75 volts. If ground and green connector are removed the relay goes to 12.75 volts.

Yes, the BAS is bypassed with the outside wires connected and the middle wire loose.
 

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I would have to see the manual to see what these plugs are. maybe someone has the bike and knows what they are for.
 

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Discussion Starter #17 (Edited)
Looking at the manual the green plug is the side stand switch plug. I just find it weird that it only does this if the grounds are removed as well. If I leave the ground connected it doesnt change anything.
 

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If you are removing the ground wires from the frame that isn't going to help because that is where the ecm is getting the ground to trigger. You need to trace the ground wire from the fuel pump relay. When you turn on the bike and put it to run the ecm will engage the ground to the fuel pump relay and that will turn it on. If you have the manual it has pin diagnostics to check to see what is wrong with the fuel pump/ecm to find the problem.
 

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Discussion Starter #19
I went through and tested everything and everything worked right via continuity testing. Started tracing wires and noticed a rub mark on a set that looked like nothing. Decided to cut the insulation/wire wrap away and the BAS wires had been cut about 1.5 feet back from the connector during the fall. Spliced the wires and it fired right up.

Thanks for all the help and suggestions.
 
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