Dyna s problem

i started having a problem a couple moths ago where i would ride and cylinders 2 and 3 would cut out at random. i thought i solved the problem when i fixed some connections. however, i went to start my bike up today and cylinders 2 and 3 wont fire. i have a dyna s ignition system and accel coils (installed by PO), and the bike ran beautifully a week ago. i believe i have the problem traced back to the dyna s. i had no spark to cylinders 2/3, but when i switched the power wires going to the coils i got spark in 2/3 but not 1/4. the left dyna s module is supposed to fire 1/4 correct? when i have the left hand module going to those cylinders, nothing, but when i have the right hand module going to the coil that powers 1/4 those 2 cylinders fire, but not 2/3. could one of the modules be faulty? i have a 79 kz650 c3 by the way.

Have you went to their Website and downloaded the trouble shooting yet? Complete that first then call Dyna. The hold time is long but they have a great bunch of guys.
www.dynaonline.com/skins/downloads/

That's a pretty damming indictment on the Dyna-S module plate.

I think you have it well in hand and mostly solved, but spend the extra time running it all down again, listen to the forum advice.

Don't get tunnel vision and miss something.

kaw-a-holic wrote: Have you went to their Website and downloaded the trouble shooting yet? Complete that first then call Dyna. The hold time is long but they have a great bunch of guys.
www.dynaonline.com/skins/downloads/

Speaking of Dyna S, before I call them or wait for an email reply.
I have heard of guys sending them the units to test and diagnos.
Anyone know what they charge?? I have 3 Dyna S units that have been sitting for many years.
This was an old pic. when I was selling bikes last year.
Priority back & forth only $11, I can send them a prepaid return mailing package.

by your description ,it does sound like you have a bad dyna s module.......... :ohmy:

z1kzonly wrote:

kaw-a-holic wrote: Have you went to their Website and downloaded the trouble shooting yet? Complete that first then call Dyna. The hold time is long but they have a great bunch of guys.
www.dynaonline.com/skins/downloads/

Speaking of Dyna S, before I call them or wait for an email reply.
I have heard of guys sending them the units to test and diagnos.
Anyone know what they charge?? I have 3 Dyna S units that have been sitting for many years.
This was an old pic. when I was selling bikes last year.
Priority back & forth only $11, I can send them a prepaid return mailing package.

Check with em but I remember they told me around 80 dollars plus postage when one of my module burnt out and that was in maybe 03 or 04. I threw my points back in and went with a new one after the rebuild.

KZB2 650 wrote:

z1kzonly wrote:

kaw-a-holic wrote: Have you went to their Website and downloaded the trouble shooting yet? Complete that first then call Dyna. The hold time is long but they have a great bunch of guys.
www.dynaonline.com/skins/downloads/

Speaking of Dyna S, before I call them or wait for an email reply.
I have heard of guys sending them the units to test and diagnos.
Anyone know what they charge?? I have 3 Dyna S units that have been sitting for many years.
This was an old pic. when I was selling bikes last year.
Priority back & forth only $11, I can send them a prepaid return mailing package.

Check with em but I remember they told me around 80 dollars plus postage when one of my module burnt out and that was in maybe 03 or 04. I threw my points back in and went with a new one after the rebuild.

Mine was still under warranty so it only cost me shipping to them. The trouble shooting determined what was wrong, bad module. They had to test it to replace it for free. There tech support is over the phone is free. Email support takes forever and would not suggest it. Had my replacement parts by the time they emailed me back for support.

Did you happen to crank the engine over while the sparkplugs were out? That will fry a module really quick.

holmes wrote: . . . no spark to cylinders 2/3, but when i switched the power wires going to the coils i got spark in 2/3 but not 1/4 . . . .

power wires

A coil's primary winding is powered by the battery.

The coil charges while its primary winding is grounded through a Dyna-S module.
The coil fires when the Dyna-S module "ungrounds" the coil's primary winding.

With wires connected normally, and ignition switched ON, is full battery voltage being received at both ignition coils?

Good Fortune!

baldy110 wrote: Did you happen to crank the engine over while the sparkplugs were out? That will fry a module really quick.

I believe Dyna says to pull the plugs and spin the motor over to check for spark.

I just started having this problem yesterday. I should have looked before starting the thread I just started which basically states your exact same problem. Let us know if the new plate fixes things!

sbc1320 wrote:

baldy110 wrote: Did you happen to crank the engine over while the sparkplugs were out? That will fry a module really quick.

I believe Dyna says to pull the plugs and spin the motor over to check for spark.

Dyna does say that but if you pull all the plugs and test one cylinder at a time for spark without plugs in the remaining leads, grounded out you will blow a module.