No signal from (new) Dyna S. Is my ignitor box dead?

[psyguy]

Hi guys. Long time no see... I've been active on here like a decade ago or more... Anyhow, I still have my 1980 GS850G from that time.

Bike dropped cylinders 1&4 recently. First intermittently, then for good.
I've got new Dyna green coils (with coil relay mod) and a new DynaS signal generator installed. But one of the two wires coming of the Dyna does not produce signal (tested with the probe light).
So, what do I test next and how?
Thanks

20211002_173452.jpg

[psyguy]

This is what my igniter looks like:

20211002_173224.jpg

[timebombprod]

if you havent deleted the ignitor that goes inbetween your dyna signal generator and the coilpacks, it kindove defeats the purpose of the dyna. the ignitor is meant to be deleted and you run a hot wire to the dyna via the killswitch to give it power, but since you have a coil relay mod, you have basically done that. i would delete the ignitor unit personally. as for the dyna possibly being the issue, all you can do is run a resistance test along your points with the corresponding wire and get a reading of bare minimal to no resistance, unfortunately thats the only way you can really test a dyna in most cases they just ask for it to be sent out and checked.


i guess i should ask did you rotate the motor while checking for a signal being generated from the dyna s? if the circuit is open on one of the points you most definently will not get a current.

[psyguy]

if you havent deleted the ignitor that goes inbetween your dyna signal generator and the coilpacks, it kindove defeats the purpose of the dyna. the ignitor is meant to be deleted and you run a hot wire to the dyna via the killswitch to give it power, but since you have a coil relay mod, you have basically done that. i would delete the ignitor unit personally.

I wasn't aware you could delete the Ignitor. How do you do that - how do you wire the DynaS signal wires (given I have the coil relay mod already in place)?

as for the dyna possibly being the issue

I've tried two different Dyna signal units (as I had a spare). One is completely new. So, not likely they both have the exact same failure.

i guess i should ask did you rotate the motor while checking for a signal being generated from the dyna s?

Yes, I did it with the motor running on two cylinders. I get a flashing probe light on one wire from the dyna, but not from the other. I put the probe on the single connectors where the Dyna wires join the wiring harness (as per the pic posted).

[timebombprod]

okay, honestly just from hearing you say you have installed 2 different ignitions and they both have failed the same two cylinders, you are right more than likely its not the ignition unit itself more than likely it is the ignitor.

deleting the ignitor you would just hook up the dyna wires to your coil wires that originally were connected to the ignitor unit. now i cant remember exactly which go to which but its pretty straight forward, if you look at how dyna wants you to install the ignition directly to the coil pack you can just back track it and go to the wires it routes pretty close to how the original wiring route would be. id check my bike but i left it at my buddies house for the night i didnt want to put my gear back on stinking like fish lol.





its been a while since ive done this stuff darnit. id be able to tell you how the coil mod went without the ignitor box. really all i can remember without looking at the bike is that there was a splice that had to be undone and one of the wires involved was the killswitch.

tomorrow will be the day i can let you know exactly how the routing goes.

[psyguy]

I've checked the factory Ignitor box and while it was plugged in it wasn't actually doing anything. So, I have discarded it. Silly me, who knows what I was thinking when I was wiring this 13 years ago!
The Dyna S is wired as per their wiring diagram (attached) except that it gets powered from the coils relay, as visible on the pic in the first post (above).
Coils relay mod is in place - the relay gets triggered by the wire from the kill switch and a direct line from the relay powers the coils.

Anyhow, I kept testing and discovered that if I test each signal wire from Dyna S separately (while only one of them is plugged into the harness), and by putting the test light at the coils and rotating the crank (with the power ON) I do get the test light to light up. So, one wire at the time works fine.
But when I connect BOTH wires into the wiring harness (going to the coils) only one gets to the produce signal/light as I keep turning the crank (cyl 2/3 ok, cyl 1/4 not). I tested this with both Dyna S ignitions and got the same results (one Dyna S is completely new).

BUT THEN, as I kept fiddling with the wires, etc. I was able to get the test light alternatively on one wire then the other while both of them were plugged in (as it should be).
So, I cranked the engine and sure enough it started on all four cylinders. So, I'm back to this being an intermittent problem, the way it started. I haven't really "fixed" anything so the prob is bound to come back...

Any ideas on what could be causing it?

Capture.jpg

[timebombprod]

https://youtu.be/RP6GG8EYCoE

heres the setup, coil relay mod, dyna ignition, ignitor delete. hopefully this helps!

[psyguy]

Thanks for that!
My bike is wired exactly like yours.
Having slept on this, I'm thinking since I've eliminated the coils and the Dyna ignition module as possible causes - as the same symptom appears with new coils and new Dyna S - the only remaining part is the wiring. Possibly one of the signal wires (going to the cyl 1-4 coil) may have a slight break in it, inside the wiring harness, causing intermittent problems?
I think I'll run new wires from the Dyna S (black and white wires connectors) to the coils, and see if that helps.

[timebombprod]

great idea, and the cheapest one too

[gs11ezrydr]

Thanks for that!
My bike is wired exactly like yours.
Having slept on this, I'm thinking since I've eliminated the coils and the Dyna ignition module as possible causes - as the same symptom appears with new coils and new Dyna S - the only remaining part is the wiring. Possibly one of the signal wires (going to the cyl 1-4 coil) may have a slight break in it, inside the wiring harness, causing intermittent problems?
I think I'll run new wires from the Dyna S (black and white wires connectors) to the coils, and see if that helps.

Now your heading in the right direction I think..Had a few Dyda S units act weird..too..

[psyguy]

I've run new wires and connectors from the coils to Dyna S and all seems to be well for now. Have only done approx. 100km so far but no probs. Definitely need to test it on a longer ride and on a hot day - that's when the probs started appearing.
I ditched the old ignitor and in it's place fitted a new fuse box that I use for the auxiliaries (heated grips, phone charger, battery minder, plus one spare fuse).

20211011_124304.jpg

[psyguy]

Now your heading in the right direction I think..Had a few Dyda S units act weird..too..

Yeah, new coils, wires, connectors - so if there's any strange business happen now, then it must be the Dyna S playing up.