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Discussion Starter #1
So after adding wheels, CF parts, Brembo bling and so on, I had the old girl running a couple months ago. Then I got an attack of stupid and decided to give some aftermarket coils a try. That turned into a 2 month long mission and after all sorted out I went to start and no start. She's spinning but no start. Checked the coil wiring and looks good so next try I'm like, what? No pump prime! Book says for 2002 RC check for battery voltage at the pump plug wire harness side, should have battery voltage for a few seconds. I have battery voltage but it's constant. Would this indicate fuel cut relay problem? I swapped with another relay, I also tried battery power to pump plug but no dice. Help me Obi wan you're my only hope. :surprise:
 

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which wire did you measure for voltage on? you may have been misreading on the thermistor instead of the feed to the pump?



when you turn the key on does the FI light come on for a few seconds on the dash, then go out? if it does, then the fuel pump should prime, if it doesn't, then you have other issues we need to address first.



report back
 

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Discussion Starter #3
Thanks for quick reply. I measured 12.4v at the brown wire with black tracer & green wire. Also checked continuity from same br/bl wire from relay to plug at pump connector and was good. Fact that voltage was constant tells me no bueno. The FI did not come on when I turned key on. I have a used ECU and rear sub harness but were purchased online and never verified if ECU good yet. Just stocking up spares as new parts starting to dry up.
 

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If the FI light did not come on with the key on. The ecu is not powered up..

Check your kill switch and bank angle sensor
 

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The brown/black at the fuel pump connector is not the power wire. It's the fuel level sensor wire. If the thermistor in the tank is cold you'll see 12 volts on that wire. When the thermistor warms it lowers its resistance and connects the brown/black to ground and illuminates the low fuel lamp.

The power wire for the fuel pump is brown.



The brown black you were checking at the relay is not the power wire for the pump either. It is the negative wire from the coil on the relay. It goes to the ecu. When the ecu grounds it, it turns the relay on




So as I said, check your kill switch and bank angle sensor. Your engine stop relay is not pulling hence the no FI lamp with key on. This may not even be a fuel pump issue.
 

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Discussion Starter #6
OK so then the brown wire had no current. I did trim some plastic from the kill switch as the master cylinder was close and I wanted to give a little room there. That was a while back but very possible stressed a wire there. Will check in the AM and report back. Appreciate your help.
 

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With the key on, toggle the kill switch on and off. You should be getting a click from the engine stop relay (two reds and two blacks)

If you aren't, the issue is either a fuse or the kill switch or bank angle sensor. The kill switch can be bypassed by shorting the black/white and white/black at the 9 pin red connector on the right side.

The bank angle sensor can be bypassed by shorting the red and green wires in the green 3 pin connector on the left side of the tail section.
 

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Discussion Starter #8
Sorry, caught caught up in all our mid term election craziness this AM. Back in shop and checking out per your post.
 

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Discussion Starter #9
Relay is clicking. performed bank angle voltage check as per manual & 12.7V between green & white, .3V between green & red.
 

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If the FI light doesn't come on then the ecu isn't powering up.


Try swapping the engine stop relay for the high beam relay.


If you have a multimeter you should check for 12 v (red lead on wire, black lead on battery negative) on both wires on the contact side of the relay (looking at the bottom of the relay with the locking tab facing up, the two wires on the left) when the kill switch is in the run position.
 

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Discussion Starter #13
Swapped relays. Voltage at .048 for both contacts on left side with lock tab at top or facing up.
 

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so with your red lead of your meter on the red/white wire, and the black lead on batt negative, meter set to VDC you get nothing? same test done on the black/white gets you the same result?



is the 30 amp EFI fuse in tact? it's in the small white case near the battery, similarly, is the single wire connector near this fuse plugged in? you have no power to the EFI system based on what you're telling me.
 

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Discussion Starter #15
On the red/white I have .048V and same for black/white. The black wire has 12.5V and the red has .5V. In my shop manual these are the bank angle sensor relay wires. I don't have the fuse anymore as I went to the Shindengen 847 series regulator which Roadstercycle supplies with an auto resetting circuit breaker. There is 13.3V on that wire which comes from the regulator. They do eliminate the white/black wire on the stock regulator plug. It's just terminated at that point but still completes it's other circuits as measured at the bank angle sensor where I had battery voltage per SM test. Time for my evening Bombay & tonic as this sucker has me double checking my mods in this area of the wire harness.
 

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ok you messed up man


that fuse is the supply circuit to the entire EFI system, under no circumstances should it ever be deleted. if you do not have a constant 12v on the red/white at the fuel cut relay, your bike cannot work.



i believe you have messed up the rectifier installation. the red/white with the inline fuse is NOT the feed from the rectifier. the rectifier feeds directly to the starter relay and makes it way to the battery from there. it does not touch the red/white EFI feed with the 30amp fuse in line.




the readings you took on the black and red at your engine stop relay are normal. the kill switch is fed by the white/black from the ignition fuse, that wire goes up to the kill switch, where it turns into the black that goes to the coil side of the engine stop relay. the red wire at the engine stop relay goes to the bank angle sensor where it connects to ground when the sensor is satisfied. therefore you have 12v on the black as the kill switch is satisfied, and nothing on the red as the BAS is satisfied. if the BAS was tripped, you'd have 12v on the red. if the kill switch was tripped you'd have 0v on the black and the red.


because the control circuit for the engine stop relay gets power from a different circuit than the EFI, it's simple to have a working engine stop relay without power at the contacts. ie the control circuit is fine (kill and bank angle), but the power circuit is not (ie you removed the power source to the relay contacts)



hope this helps.
 

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Discussion Starter #17
Where do I send the Don Julio to? That was it. I still had the wire in the harness and only had to jump from it to the battery and the pump primed, FI light cycled like it should. Thanks man, I was hoping you would reply when I posted cause I had seen your step by step when you have helped some other members. As soon as I saw the circuit went thru the bank angle relay the lights went on in the old farts remaining brain cells, however dim.
 

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haha glad it was something easy. my last adventure with LDH ended up with my ecu traveling across the continent
 

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Discussion Starter #19
Yeah, the way his went I'm sure he was like " where do I start?" Glad I didn't rip that wire out of the harness. In the middle of this about a year ago I had installed Matts' Battery relocate kit and decided to move the starter relay down next to the battery so all my big cables were significantly reduced in length. Actually took a pound out just in wires. That's when I went into the harness to move the feed for the starter relay. I still had the red/white with the fuse intact. I got confused when I installed the harness for the series regulator. I'll tell ya I stared at the cut red wire for a while thinking this is ok right? WRONG. Ha Ha but ya got me fixed and It just took some wire and a couple of terminals. I thought I was going to need a ecu too, $600 at my local dealer although I have a used one I picked up from a salvage yard. Thanks again!
 
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