How to test the ignitor unit (CDI)

[untertaber]

Hello friends, currently still am without spark. I couldnt get a clear reading trough my spark plug cap, so I think im gonna replace it as its cheap anyways... checked my ignition coil and it was all within spec so thats ruled out! Now im down to wanting to check the 'ignitor unit'/cdi.. does anyone have any idea how im able to check wether or not its good?? It like to make sure before spending the money since a replacement aint cheap... thanks :)

[motorang]

Check the Carmo website for info, they do check CDIs as well when sent in, may be cheaper to get a functioning one off Ebay though. Only way I know is to put it in a bike ...
https://www.carmo.nl/index.php?main_page=page&id=35

The Transmic website gives some more insight:
https://transmic.net/2016/07/14/yamaha/

Most of the time the culprit is a faulty ignition coil an the stator, sitting in the left engine cover. Or the staor wiring is damaged/brittle, so there is low insulation, which mostly happens where the stator wiring exits the engine block.

Try measuring resistance between the red and brown wire coming from the engine, CDI disconnected. This is the ignition generator coil. If it is not near 140 to 200 Ohm, you have found the problem. If the stator or CDI was swapped before the problems, you can try connect the two wires reversed, which may fix the problem as well. Some retrofit stators or even repairs do not care about the direction of winding the coil, which results in a different pulse/signal (plus instead of minus), which can be reversed by connecting brown (staor) to red (CDI) and red (stator) to brown (CDI).
You may also measure brown to ground and red to ground, both should read "open circuit" or at least very high resistance (Megaohm or higher).

Andy

[motorang]

Also for diagnosing, disconnect the black-white wire from the CDI, which does the engine shut-off via ignition switch (ignition key) and kill switch in most models when being connected to negative ground (black).

For sidestand switch, see here:
viewtopic.php?p=38871#p38871

Andy

[motorang]

Oh man, I was fooled into thinking you had CDI problems by the thread title.

If you did put your topic in the correct forum (XTZ660 Tenere Forum):
The XTZ model does NOT have a coil-powered CDI, but instead what Yamaha sells as a "digital CDI" or more commonly known a TCI (transistor discharge ignition) which is battery powered AND has a different pickup with two wires only.

So ...
post a picture of your "CDI" where I can read the printed numbers, and we can go from there.

CDI is brown and flat, and has a wiring loom
https://www.xt-foren.de/xt-phpbb/downlo ... hp?id=7477

TCI is black and elongated and has recepticals for the engine wiring loom connectors.
https://www.xt-foren.de/Files/40a355e91b80ddcb.jpg


Andy