RPM & CHT on Odyssey G2 Rotax 912UL

[Gareth H]

Long story short, I've had to remove my 912is and install a 912 UL with a big bore piston kit.

I've had to remove the 912is RDAC (Obviously). I have a RDAC XD which I installed (got it with the EFIS).

A more pressing issue is that I cannot seem to get the RPM to pick up on the EFIS through the RDAC. I can confirm that it is grounded, and I have tried removing the ballast, but to no avail. In system diagnostics, I get a code 31000 for the RPM reading? This does not change when I engage the starter - any tips? Does the motor need to be running to send the signal?

I've been having issues getting all of the readings to fall under the correct bar graphs etc. I have updated the screens and researched all of the documentation on the MGL website regarding the RDAC and Odyssey 2 and assigning the mapping.

I seem to have gotten to a place where the EFIS shows only 1 of the two CHT probes (using the bargraph set to Rotax 912 Dual senders). For the life of me, I cannot get the second CHT sensor to show a reading. I've wired the CHT sender that comes on the motor to CHT2 and followed the manual in this regard. Is it possible for these senders to go bad? Also, I can pick up this CHT sender in the diagnostics showing 2.5V which means that it is picking something up?

I have wired it as one goes to ground on the motor, the other goes to the RPM port on the RDAC...

Thanks!

[rainier]

You don't mention the EFIS model so a bit of a guess:

The standard Rotax CHT probes are NOT thermocouples. They are actually normal oil temperature NTC senders.
Thus they are connected to AUX1 and AUX2 on the RDAC and you will then configure the corresponding AUX1 and AUX2 channels to be "standard NTC" as probe type.
For the screen that means whatever you put on as display needs to get its data from AUX1 and AUX2 - so typically you would have two bargraphs and two special text items connected to the AUX1 and AUX2 numeric readouts.
Note that you would NOT use the CHT bargraph as that assumes we will be using normal thermocouple probes.
Rotax is the odd one out here with the usage of NTC senders so it gets a special treatment.

Hope that clears it up.