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Dutch85
Posted on Thursday, September 27, 2012 - 08:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So, I recently had a 2,000 dollar transmission rebuild on my bike. Two days after I got it back I took it out to street vibrations(a 200 mile venture). Then my bike broke down in Virginia City. I got a trailer and brought my bike back home to the bay area. When I got back I started to trouble shoot. I noticed my fuel pump was not priming. First thing I did was check all my fuses and all was good. Then I pulled my pump and hot wired it directly to the battery. The pump still works. I tested the connector at the fuel pump, there was 10 volts going to the low fuel sensor and zero going to the pump. Next I switched my relay box, and that didn't change anything. So on my "relay center" i tested continuity between outlet 5 and the connector at the pump and there was no short or break in the wire, although it was a different story between outlet 4 and the fuel pump connector but I believe this is fine because outlet 4 is the "feed" side, and is only suppose to send power when connected to 5 via the relay. So here's where it gets weird. If I jump outlet 4 directly to outlet 5 my low beam turns on(this low beam stopped working at the exact same time as my pump). Then I checked voltage I was getting 10 volts to both the pump and the low fuel sensor. 10 volts isn't enough to power my pump though, it needs 12. I split the relay center open to take a look at it, didn't notice anything too abnormal, but when I put it back together jumping outlet 4 and 5 no longer did anything.

Any ideas one what to try next or check out next to get this problem solved?

Thanks
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Dutch85
Posted on Thursday, September 27, 2012 - 10:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

in case you're wondering where these 4 and 5 numbers are coming from here is the wiring diagram I'm following.

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Dutch85
Posted on Friday, September 28, 2012 - 04:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

my pump is once again receiving 10 volts but my pump is not priming with only 10 volts.
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Rays
Posted on Friday, September 28, 2012 - 06:15 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I have to confess that your symptoms are very confusing. In the posts you have put on another forum about this you state that there is continuity between point 4 (the 87 pin on the ignition relay) and the fuel pump connector (grey wire) - this is correct. Point 5 (pin 30 on the Ignition relay) should have power provided via the Ignition fuse.

I don't pretend to be an expert but this is how I would approach this.

1. Assume nothing - you might get lucky but these things need a careful course of analysis and elimination.
2. Check what the current battery voltage is - it should be very close to +12v assuming you haven't run it down a lot by attempting to start. You need to make sure you aren't chasing ghosts when you measure a lower voltage at other points.
3. Double check the battery terminal are clean and tight - you would be surprised at how many of these electrical diagnosis threads end up back at the battery connections.
4. Remove the ignition fuse and with the ignition switch in the ON position measure for +12v (battery voltage) at the fuse.
5. If you do have +12v at the fuse then there should be +12v at point 5 (pin 30 on ignition relay). If not then check that wiring.
6. If you don't have +12v at the ignition fuse then that is provided by the keyswitch relay (point 14 on your diagram).
7. Assuming you do have +12v at point 5, the killswitch provides the power to activate the Ignition relay and when that energises you get the ECM powered and that toggles the engine light on the dash and runs the fuel pump for 3-4 secs. (you might recall I asked you on the other thread whether or not the engine light toggled - it was a valid diagnostic question).
8. measure the +12v provided by the killswitch on point 1 on your diagram (pin 86 on the ignition relay).

Can you measure some of these voltages and that will determine where you head next. It would take me all day to try and produce a foolproof list of things to check.
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Dutch85
Posted on Friday, September 28, 2012 - 07:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'll take a stab at trouble shooting these steps tomorrow night, I got to get to sleep for class tomorrow afternoon. And I do have to say part of the issue was that my ignition fuse was rattling around causing stuff like my lights and the voltage to my pump to go in and out. Now my next problem is that even with 10 volts the pump is still not priming. if I plug the grey wire into my pump then ground the lead on the pump that originally plugs into the brown and yellow wire the pump kicks on. This is the "feed" wire from outlet 4 that was showing continuity issues. Thanks for all your help Ray and I'll get back to the post tomorrow after I try your trouble shooting suggestions.

(Message edited by dutch85 on September 28, 2012)
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Reepicheep
Posted on Friday, September 28, 2012 - 08:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The 10 volts is the whacked out part. It should be either on (12.X v, .x within what the battery reads), or off (0.x v).

10V on the pump relative to 12v on the battery is really weird, especially if nothing is hot or smoking at the time. (A partial short in the pump could be drawing so much current that the voltage is dropping, but that would be a LOT of current, and something would be hot or on fire as a result).
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Dutch85
Posted on Friday, September 28, 2012 - 06:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Do you think it's a bad ecm? My buddy has his original stock ecm, so I'm going to see if I can get it from him him and just test it out.
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Reepicheep
Posted on Friday, September 28, 2012 - 07:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't think so. The ECM would want to turn the pump on or off. I don't think it has a "half on" mechanism.

I assume there is a relay to drive the fuel pump, I'd start there.

(and make sure you are measuring voltage right, meters can get confusing)
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Dutch85
Posted on Saturday, September 29, 2012 - 01:40 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

1.
2. 11.93
3. good
4. 11.83
5. 11.83
6.
7. my check engine light does not come on.(sorry, in the other thread I thought you were saying to try different relays in the ignition outlet of the relay center and check if the check engine light came on because that would mean that relay was bad)
8. 11.83 volts are on ignition outlet 1 at the relay center.

thanks for the help so the only diagnostic test it failed is no check engine light but there is power at the relay center.
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Dutch85
Posted on Saturday, September 29, 2012 - 01:47 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ok here is the messed up thing if I test the voltage between grey and brown/yellow at the pump I get 10 volts, but if I ground it out some where else(other than the brown/yellow) then I get 11.27 and the pump works. I tested continuity between brown and yellow at the ECM and and brown and yellow at the pump and it is fine.
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Rays
Posted on Saturday, September 29, 2012 - 02:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

OK, that makes more sense - when you say you measured 10V and didn't give a 'with respect to' reference the assumption is ground.
The brown yellow wire goes to the ECM so measuring between the 12v source and that wire is not something I know off the top of my head.
I will go and check it on my '06 Uly now and see what the result is just for interest.
What you have verified though is that you are getting +12v supplied to the pump and you have already hotwired it to prove it is OK so the ECM isn't switching it on.
THe tests you have done indicate the Ignition relay is being turned on and presumably supplying power to the ECM as that is common to the Grey wire going to the pump.
The last thing you could verify is that when you turn the kill switch to RUN that +12 v (11.9 in your case) is getting to pin 1 on the Black ECM connector (Grey wire as well).
What should happen when the ECM gets the switched Ignition voltage it goes through the start-up that outwardly are indicated by the Check engine light going on for a few seconds and the fuel pump being run for a few seconds.
If you are getting that voltage to the ECM then the other thing to check is that the ECM is actually grounded properly - measure that pin 11 on the black connector has a good connection to the battery negative.
If you getting both of those then the ECM is a possibility - disconnect both ECM connectors and make sure the pins are clean. I have heard of someone having connection issues with these connectors on an older bike.

Don't despair yet, half the game in diagnosing electrical gremlins is proving what is working and working the gremlins into a corner.
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Dutch85
Posted on Saturday, September 29, 2012 - 02:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I guess 11.9 is lower than I thought the manual says the 11.8=0% charge
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Rays
Posted on Saturday, September 29, 2012 - 03:44 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I just checked my '06 Uly and there is 10.4v between the Grey and Yellow/Red wire on the fuel pump connector.

I don't know what the internal circuitry of the ECM is exactly but this is pretty close to what you are seeing. You should see it slightly higher for the few seconds the pump would run (when that is working).

When I mentioned measuring the ECM voltage it is a lot easier than it looks 0 the rear of the ECM plugs is very soft to seal on the wires so you should be able to slide the multimeter probe into the back of the pin like this:



For the ECM ground check I had to put a pin into the socket because my meter probes are i little too big. Note that I disconnected the battery before doing this check. Probably not strictly necessary but old habits die hard.
CHeck what zero really is on your meter before starting (in my case my Fluke is 0.2ohms with the leads shorted so this measurement is actually close to zero.



You can see my '06 battery is even lower than yours - I haven't ridden it for weeks and the battery is few years old.
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Dutch85
Posted on Saturday, September 29, 2012 - 04:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

so after I noticed that my battery was pretty low, I decided to put it on the trickle charger. So my ECM is getting 12 volts to the grey wire then I checked both system ground A and system ground B on 2 and 11 and they are properly grounded. I guess the only thing for me to do now is wait until the morning when my buddy is suppose to bring through his old ECM

Thanks
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Reepicheep
Posted on Saturday, September 29, 2012 - 07:53 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The manual's list of battery voltages and what capacity that translates to is pretty much fantasy, so take that with a grain of salt.
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Dutch85
Posted on Saturday, September 29, 2012 - 02:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

plugged in the ECM my friend dropped off and it still didn't work
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Dutch85
Posted on Saturday, September 29, 2012 - 09:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

well, my bike is actually running now but my check engine light came on and it bogs at low rpms(around 2k to 4k) if I put it in neutral and rev at 5k for about 10 to 20 seconds my check engine light turns off. I have a feeling it might be from the fuel lines airing out for about 4 to 5 days. something similar happened when I replaced the fuel filter in my triumph. It took about 30 to 50 miles for the bike to run normal again.

by the way, I guess my ECM fuse was corroded. I tested it to make sure it was still good and it was, but once I put in a new fuse it started up.

Thanks for all your help guys
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Rays
Posted on Sunday, September 30, 2012 - 03:22 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Result! - well done.

I was actually surprised at how grotty looking my EMC pins were when I removed the connectors for the photos I took yesterday - slight corrosion can be a nuisance.
Looking back at the sequence of events I did see you had checked the fuses right at the beginning but when the check light wasn't coming on I didn't get you to confirm the ECM 'Keep Alive' was present.
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