No spark

[lawrie]

Gentlemen, I'm in a bit of a quandary, went to run the 14s round the block yesterday, 1st one fine, second, spins over nice & fast, but no go, pulled the plugs, ZILCH, so i'm assuming there's no feed to the coils.

Checked the codes, nothing came up, fuses fine, went for the CD unit, then remembered there aint one!!

Turn key, full needle sweep check, can hear pump running & priming, engine spins fast, so the CDi unit is obviously part of the main ECU.
I THINK the ECUs can be swapped over to check, but can any of you gurus out there confirm that it is safe to do so, as I don't wish to make things worse!!

[KiwiCol]

That's a real odd one Lawrie.   I'm no gentleman or guru, so mine is only guess work, but could it be a fuse? or disconnected plug somewhere?

[Blubber]

You can bypass the clutch switch see if its just that?

[Timothy Spencer]

If it spins over then the clutch, stand and kill switches are likely to be all fine.
Corrosion in the wiring connectors would be my next thing to have a good look at along with some multi meter work to see where the leccy is going or not.
One thing is clear and that it is something common to all plugs

[Hooli]

K2-K4 ECUs can be swapped with no issues.

K5 onwards I think you'll need to use the key that matches the ECU for the immobiliser.

You can't swap pre-K5 with K5 onwards as the plugs don't fit on the ECU.

[gsxbarmy]

maybe check the low tension lead Lawrie

[Hooli]

Both of them as I'm pretty sure the coils fire independently of each other. I wonder if they have a common earth??

Do the plugs come out wet? If not then I suspect the ECU is registering the engine turning to fire the injectors either, but I'd expect a code of the crank sensor had gone as it'd still see movement in the cam sensor.

[lawrie]

Thanks for replies fellas, I'm busy at the mo with other projects, but now I've been assured that the ecu's can be swapped, i'll do that first,
so if it WORKS, its an ecu problem, if the same, then i'll break out the test meter & start a series of eliminations!!

[gsxbarmy]

Don't rule out a dry joint somewhere Lawrie, had that years ago on one of my Kawasakis, and it was a dry joint on the main power lead to the coils.

[Andre]

Had no spark and no fuel pump but the starter turned. All isolated measurements I took were ok. Read online that ignition switch could cause this as well as no spark alone (continuously and intermittent). Checked the continuity of the switch as per service manual. Didn't get a beep  on B/W - O/Y. Found out later that it couldn't because of a build-in resistor on B/W (100 ohm - not mentioned in the manual).

Took the switch apart, which required drilling out of 2 break-off-by design screws. Saw the resistor which caused the continuity-beep to fail. The contacts didn't look as bad as I had seen in online pics. Cleaned them and serviced the mechanical parts. Installed the switch thinking that it was not the culprit. Cussed and hit the starter - surprise, the engine started and no problems since then.

Advice to service the "officially" non-serviceable ignition switch. A couple pics, one of the screws that make it "non-serviceable" and one of the contact plate.

[KiwiCol]

Well done Andre!    That's another detailed / clever repair. You a smart cookie for sure.

[Andre]

Thanks for the flowers Col, I am a cookie for sure, smart? well yes, but lots more smarter than me out there. I love when someone tells me "you can't do that" or "you will never get this back together". Hardly anything more motivating than this, even when having thoughts like that myself (which get banned immediately) .

BIG thanks to those who reported ignition switch "mysteries" on the net. BIG "you are disgusting in your greed" to those companies who make it difficult to repair or service their products to entice us to buy new. The switch would have cost me 140€.  Add lots more € to buy matching locks for tank, seat, and helmet holder. Now I have a smooth working lock due to replacing the microscopic amount of dried grease with a truck load of fresh stuff.

[Tug]

good catch Andre

[RickC]

Good one Andre,
I believe the resister is there for theft prevention to stop hot wiring.

Cheers,
Rick

[lawrie]

OK, so I got round to try a few things, first up, I think the ECU is good, as I swapped them over  & the 'good' bike started up & ran fine with the non-running bikes ECU, but the non-runner again wont run with the 'good' unit, if that makes sense!!
Now for the weird bit, the manual tells me to check battery voltages at various points, which I have, BUT instead of 12.5-13v , i'm getting 11.5 everywhere instead, so I seem to be losing a volt or so in the wiring, but I AM getting voltages everywhere!!
VERY careful scrutiny reviles a 'sort-of' spark now & again ( from all 4 ) so I'm assuming a common supply problem, also, if I actually HOLD a plug, I get a whack!!
Every connector has been inspected & re-fitted, they LOOK OK.
The manual specifies a 'peak-voltage' setting, so I'm assuming a specialist meter??
My meter is a high-end device, but is still a basic unit & when I did the tests, I was getting readings but not sure if they relate to the manual's  specs.
Pump runs, tried all the interlocks, clutch, sidestand, killswitch etc. etc. just no spark!!
Head scratching time!!