Reply With QuoteAlso, Barrett, you mentioned something about a fuse box diode. I don't see anything like that in the prints or in the box itself. Can you tell me where that is located?
Well, I removed the loom from the bike side at the fuel pump connector to the black ecm conn. Found the bwn/y wire splice, it looked clean and secure. I did find some insulation and wire damage on the single wire before the splice, probably caused by me removing the loom. Repaired that damage and covered with heat shrink. I removed the bottom cover of the fuse box, all looks clean and well connected in there, and no fuses every blow. I checked the ground wires for the black ecm conn, the bike side and pump side of the pump harness, all show no resistance. Loosened and resecured the grounds for the battery and the one next to the fuse box with several wires attached. With the ignition switch plug, all four relays, the bas plug and both ecm conn's removed, the pump is still powered and running. Looking at the wiring diagram, which is very confusing, it appears as Rays said the fuel pump is hot at the fuse box, and it is, as well as everything else connected to the same wire per the diagram. I guess my question is, under normal operation, what turns the pump off and keeps it from running with ignition and kill off? Since I have the ecm plug off should I try jumping the two bwn/y wires together? Getting a bit frustrated....
Also, Barrett, you mentioned something about a fuse box diode. I don't see anything like that in the prints or in the box itself. Can you tell me where that is located?
The fuse box diode is a pre-2008 item that provides isolation between the clutch switch and the neutral switch - this is handled by the ECM in the 2008-2009 so not fitted (I have no idea about the 2010).
I will have a further dig into the pump wiring on my 2009 Uly later today but in theory with the ECM black plug disconnected there is no switched ground connection possible for the fuel pump.
If the internals of the pump are definitely Ok and you have verified the physical wiring from fuel pump connector to ECM connector then the only thing I can think that might be wrong (it is a wild-arse guess) is that the ground and fuel pump switched ground wires are swapped in the fuel pump/main loom Deutsch connector?
That would give you a constantly running fuel pump and a low fuel light that may or may not work depending on what sort of ground the pump body found though the physical connection to the frame.
I confess that is highly unlikely but very easy to eliminate.
Are you comfortable with de-pinning a Deutsch connector? - if not please let me know and I can post up a quick tutorial.
However, assuming the wires are connected like for like in the fuel pump connector and you still have the issue, I would disconnect the Brown/Yellow wire (pin 4) from the loom connector as another isolation step.
Note: be very careful playing around with the pins in the fuel pump plug given the FP power is hot - very easy to short that out. I would suggest removing the fuel pump fuse at least before opening up the loom side plug if you decide to do that.
Ray
I had passed along info to you, supplied to me, from the factory. One small portion of it mentioned diode placement. If the DDFI-3 electronics and ECM system don't use it as Ray mentioned, then clearly not a consideration for you.Originally Posted by ajax5777
Regarding your question "what turns the pump on and off"? Your ECM does, via the "trigger wire" which, for your pump, is the Yellow/Brown wire. The trigger wire completes the circuit to the pump electric motor via ground and switching it ON. Seems evident this critical problem existed when you purchased the bike. With everything unplugged that you listed and 10A pump fuse remaining IN place and the pump continuing to run, the reason is quite simple and can only be caused by 2 possibilities: The pump has either found its own ground signal......OR the PO prior to your purchase, installed a pre-2008 new or used pump assembly which has different wiring orientation because the pump-to-harness plug is different. PO clearly would have known this problem existed when he sold it to you. Contact him and ask specifics about the pump.
In conjunction with what Ray mentioned, if the bike were here in my shop I'd simply do the following:
Check the pump plug wiring orientation vs. the harness connector plug wiring orientation and see if they are identical.
If so, then I'd remove the pump assembly from the frame, replace the pump motor and closely check the internal pump wires for chafing or shorts to the grounded pump assembly, and prior to reinstalling the pump assembly into the frame, plug the pump into the harness, turn on both KEY and KILL switch and see if problem resolved. That would be my procedure.
[QUOTE].OR the PO prior to your purchase, installed a pre-2008 new or used pump assembly which has different wiring orientation because the pump-to-harness plug is different./QUOTE]
John, If I was a betting man I think that would have my money - I just checked a 2006 pump and given the pump wires are all the same colour and function but a very different orientation in the 4-pin plug it would be pretty easy to screw up.
For ajax5777, this is a shot of an original '09 Uly fuel pump connector for reference. (it is a Deutsch DTM connector).
IMG_2365.jpg
Ray
First off, I REALLY appreciate both of you taking the time to help me t/s this problem. I just looked at the harness and the pump side is the same as the picture and matches the bike side of the harness. The only difference, and don't think it makes any difference is the gray wire in the pump harness matches up with a kind of light orange with white or gray stripe on the bike side. The other three match up with same colors so the gray has to be correct by default. I had already considered that it could just be a bad pump as I had already inspected the pump wiring and heat shrinked them to prevent chaffing. So I guess either the pump is shorting/grounding internally or could it possibly be the harness is shorting where it goes through the the pump mount plate grommet? I think when I pull the pump it would make sense to push the grommet out and check the wires condition. Another thing I didn't think to check with the pump out was if the wires were connected to the proper spades. Please let me know if you think there is anything else I could check while I have the pump out. When I did have the pump out it appeared someone had been in there before me. Quantum has a pump kit for $80 and I will get that going today. Fingers crossed...
Or do you have a better recommendation for a pump kit?
[QUOTE=Rays;635595]As I understand it, in 2010 the fuel pressure regulation was handled via PWM from the ECM. If this is a late 2009 which may have had the this feature, it would explain why is being weird. Also, as I understand it, the 2010 models had a diode to dampen the inductive spike associated with a PWM circuit..OR the PO prior to your purchase, installed a pre-2008 new or used pump assembly which has different wiring orientation because the pump-to-harness plug is different./QUOTE]
John, If I was a betting man I think that would have my money - I just checked a 2006 pump and given the pump wires are all the same colour and function but a very different orientation in the 4-pin plug it would be pretty easy to screw up.
For ajax5777, this is a shot of an original '09 Uly fuel pump connector for reference. (it is a Deutsch DTM connector).
IMG_2365.jpg
Ray
Also, bear in mind that I have never even seen a 2010 Buell, and this is mostly gleaned from internet knowledge, which can be sketchy at best (unless its from Principal Barrett Strickland).
My pleasure and I know Ray will appreciate the kudos as well. He's a great guy from OZ and is absolutely brilliant with these sort of things, as well as a host of other mechanical pursuits. I have a 2009 in my shop right now. Let me check the wiring harness for you, as Ray did, and confirm what you mentioned re gray to orange-ish wire grouping.
Absolutely hate to slam any outfit on here but I'd be very hesitant to buy a "rebuild kit" from Quantum. If you're going to keep this Ulysses and go to the major work of a full pump R&R and rebuild plus bench testing, then rebuild with correct quality components. Quantum regulators...pressure hoses....electric motors....have questionable correctness and quality. Either myself or Chaz Aagaard from Aagaard Foundry can fix you up with a full complete correct kit. They're not cheap.
I did come across the Aagaard kit. And yes not cheap but complete, including the low fuel sender. I agree, if I'm going to be in there, again, use good parts for the long haul. Thanks for the feedback on that. Will let you know how it all works out.
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