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Right CHT not working 912ULS

amekler

Well Known Member
Patron
I did my first engine start today. All went except no right CHT.
I swapped the right and left sensors and still no right cht. What should I do next to troubleshoot?
A. Mekler
 
Sounds like a connector/electrical issue. I’d start wiggling connectors to see if you can find a loose one.
 
Try putting an ohm meter on the pin at the connector to your MFD and the connector forward of the firewall to check continuity.
 
No CHT or CHT zero?

Just to clarify: "no CHT", does that mean there is no CHT at all displayed, or is it that there is a CHT but it does not go up when the engine warms up? If it is the former, then check the EMS configuration for two CHTs enabled. Otherwise check for electrical continuity from the sensor connector back to the EMS, as others have said.
 
The right cht display has an X through it.
I checked the voltage at the wire going to the sensors both were 5.0 volts. The left CHT connected and reading normally shows 3.0 volts but the right CHT
only .365 volts. As I said before I swapped sensors so it isn't the sensor.
My thoughts are the problem must be in the wiring to the EMS-200.
This harness came prewired .
Hopefully today I will pull apart the panel and see what's going on .
Alan
 
Its possible that a pin got pushed back in the D-sub connector. If pin isn't seated well in the plastic housing it can slip when force is applied.
 
pins in the correct places andcseated
wires intact
both read the same ohms
sensors both work
talked to Dynon-maybe a problem within the EMS-220

Alan
 
After installing software version 16, my Engine Management System (EMS) disappeared. I tried a fix suggested by someone on this forum, and, the EMS came back; except for the right cylinder head temperature (which has a big red X thru it).

Called Dynon and the tech rep put me thru some paces and we found there was no information getting to the CHT-R. Tech suggested switching the left CHT wire to the right CHT to test the right sensor. If that didn't work, then he thought there was a wiring problem.

I did what the tech first suggested and found the right CHT sensor is working fine. I have been looking at the wiring in the engine compartment and can find nothing wrong with the wiring. Then sprayed some electrical contact cleaner on the right sensor and the clip on the end of the wire and wiped everything clean. Have not been back to the hangar to see if the cleaner got the CHT-R operational. If not, I'll look in the avionics bay to see if I can find a wiring problem.

As background, my RV-12ULS originally was partially built with wiring for the D180. Then the nice Skyview came out and I decided to upgrade in mid-build. Van's Aircraft provided a conversion harness. I remember something did not work and Van's tech guys had me move one pin in one of the connectors - everything worked beautifully until this software version 16 came out. Now I am pondering if there is a wire that is bad, or, is there a small group of us with the conversion harness that are having the same problem? And, maybe it is related to the software 16?

Let's stay in contact.
 
chuck,
,
I called Dynon yesterday as I see no wiring issues. they want me to send a photo of the sensor debug page. I think the problem lies in the EMS-220. This was my first engine start. Now after seeing your post I wonder if it is a configuration issue
Stay in touch.

Alan
 
today I went to the sensor debug page and noticed that right cht was in pin 11 not pin 22 as it supposed to be
called vans and they recommended redownloading the set up files and reinstalling
will try that tomorrow
 
today I went to the sensor debug page and noticed that right cht was in pin 11 not pin 22 as it supposed to be
called vans and they recommended redownloading the set up files and reinstalling
will try that tomorrow
 
Alan,

Going to my EMS Setup>Sensor Data and looking at C37 P10 CHTR I see a value of nan (not available number). If your re-installing the setup files puts a number in here, please let us know.

Also, I have been perusing the Dynon forums and found a couple of people with red Xs thru the CHT-R and/or EGT-R. Their solution was finding a loose engine grounding connection, which eliminated the red Xs. They say the engine grounding cable attaches to the lug on the starter frame, and, another wire runs from the starter frame to the battery box. I'll check on this the next time I am at the hangar. In the meantime, you might give this idea a try.
 
well chuck I tried putting the file from vans on again as suggested and now I show Ems fail and a hugered x and no EMS
I rebooted the sky view and it got caught in a cycle of updating archives and never came back on. after multiple calls to Dynon and vans have to ship the sky view back for a factory reset and start all over again. Not great when I'm trying to get my DAR to inspect. Dynon says 2 -3 week turnover.

Alan
 
Alan,

That is ugly. Sorry to hear about your misadventures.

Yesterday I checked the grounding wires from the battery negative terminal to the battery box, and, from the batter box to the starter. Connections looked solid as a rock, and, no wear issues on the wires.

Carefully clipped a couple of zip ties off that were holding the CHT-R and EGT-R wires in the engine bay. Checked my Skyview monitor. Now I have Red-Xs thru both the CHT-R and EGT-R on the Skyview Engine Management System (EMS). That left me with a big question mark on my face. Went back to the engine bay and examined closely the two wires I had just freed from the zip ties; could find nothing wrong.

So, now I sit here pondering again.
 
got a call from dynon
a corrupt file had messed up the sky view
dynon was kind enough to install the needed files
I have let Van's know of the issue and they are looking into it
Alan
 
Sent some downloaded files to Dynon. Then, yesterday, Don Jones of Dynon Support, walked me thru moving the CHT-R from pin 10 to 22. Viola! The CHT-R no longer has a big red X thru it.

Don also gave me some ideas on how to resolve the problem of a big red X thru the EGT-R. With his first idea I found the sensor wire was broken. Ordered a new sensor and wire from Dynon.

The Dynon Support guys are great! In thirty minutes they diagnosed and helped me resolve a couple of problems that I spent weeks on trying to resolve. A big Thank You to Dynon!
 
Skyview back and everything works!
That's for great service Dynon.
Alan
N603NH Rv-12 912ULS almost done
 
The new Dynon Avionics P/N 100405-001 Rev L EGT Sensor, K-Type has a wire that is about twice as thick as the original part, and, is about 1" longer. Installed the new part and the red X thru the EGT-R is now gone.
 
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