How to test ignition cable?

Hi Steven

Be sure you have the latest manual, get it from Rotax-Owner or from FlyRotax.com.  You should always use the latest version for your engine type.  The pages that are current are from Issue 2 revision O, see the bottom right corner.  Download that and the electrical section is 74, page 7 shows that Ohms resistance readings quick list.  The balance of the section shows how it works and how to check individual components.  

The combined OHM readings for the spark plug wires, spark plug boots (connector) and the secondary coil is too many parts all at once.  To realistically evaluate the parts you need to check them by separating them.  In that way you can find a single failed spark plug boot for example.   The actual copper stranded wires are normally not an issue  and don't even have a specific test value.  Testing the secondary winding in the coil with them connected is normal. (just remove the spark plug boots first)  The value shown in the listing is without the connectors.

In the section you will find several other checks on the primary and secondary separately.  To do that you would have to remove the SMD modules however.  

Cheers

this may help...

Thank you again, very helpful.  Once again the page you shared is not in the latest MMH that I have (downloaded yesterday from flyrotax.com), but after looking closer at that page I now understand why.  I've been using the latest manuals labeled "912i series" since I have a 912iS, but the pages you've been sharing are from the manual labeled "912/914 series" which I assume means the non-injected versions.  I just found and downloaded that version, and found the pages you referenced (which are not in the 912i version).  I had no idea there were two versions of the MMH that covered my engine, and that I needed both...   Good to know, though!

Hi Steven

The confusion is that the thread is under the 912/914 group and not the 912iS...so the references were from that MMH.  So all good, now you know. 

Cheers

(relocated this thread to 912iS section)