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I (didn't) give up

LettersFromFlyoverCountry

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There has been no resolution to the starting problems of my RV-12iS as discussed in a thread from a few months ago.

One of the best Rotax experts looked it over today and was stumped. He doesn't think it's an injector problem because a bunch of harness issues seem to be coming into play.

There's a canbus issue. He couldn't connect to the ECU for some reason . He also found that the EMS isn't working .

He said he could understand why injectors were suspect but there's something more going on somewhere. Too many things aren't working right and if I try to start the engine again, it's going to damage it

Do I feel like tracing every wire in the Stein harness to try to find one that isn't right? I don't .

I'm beaten. I just want this thing out of my life
 

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There has been no resolution to the starting problems of my RV-12iS as discussed in a thread from a few months ago.

One of the best Rotax experts looked it over today and was stumped. He doesn't think it's an injector problem because a bunch of harness issues seem to be coming into play.

There's a canbus issue. He couldn't connect to the ECU for some reason . He also found that the EMS isn't working .

He said he could understand why injectors were suspect but there's something more going on somewhere. Too many things aren't working right and if I try to start the engine again, it's going to damage it

Do I feel like tracing every wire in the Stein harness to try to find one that isn't right? I don't .

I'm beaten. I just want this thing out of my life
Is removing the harness and sending it to Stein to trouble shoot an option?
 
One possibility here is the canbus wires are not pinned correctly. Take a look at SL-00009 and see if it may apply to your harness. https://www.vansaircraft.com/service-information-and-revisions/sl-00009/
SL-00009 sounds like a good possibility of resolution. Trying to extract the pins from the D-SUB connector and swap them might put the final nail in that project.
Just kidding, sometimes they slide out like butter with the extraction tool ... but then there's the other times :mad:
 
There has been no resolution to the starting problems of my RV-12iS as discussed in a thread from a few months ago.

One of the best Rotax experts looked it over today and was stumped. He doesn't think it's an injector problem because a bunch of harness issues seem to be coming into play.

There's a canbus issue. He couldn't connect to the ECU for some reason . He also found that the EMS isn't working .

He said he could understand why injectors were suspect but there's something more going on somewhere. Too many things aren't working right and if I try to start the engine again, it's going to damage it

Do I feel like tracing every wire in the Stein harness to try to find one that isn't right? I don't .

I'm beaten. I just want this thing out of my life
check your DM's
 
I can certainly check it but it probably does not as I didn't order avionics until June 2021 and with the pandemic supply problems I didn't receive things for almost a year.
That would put you well after the date of the service letter. However, refer to this post from Tony Kirk: (https://vansairforce.net/threads/12is-b-u-d-s-connection-issue.217113/post-1689219).

I'm sorry to inform everyone, but the Rotax Maintenance Port (CAN bus) wiring was changed on the AV-60009-2 HIC Module. This latest HIC PCB was designed using the original (correct) HIC design plans. The problem is, the previous HIC PCB had pins 14 and 15 (Maint. CAN Bus HI & Low) reversed. That was the reason for SL-00009.

The updated wiring schematic and associated Service Letter have yet to be released, I expect it will be released soon.

If you cannot get the BUDS dongle to connect to the ECU, you can swap the CAN Bus wires at the easy-to-access 9-pin Maintenance Port connector instead of messing with them in the 25-pin HIC connector, for ease of access.

If I'm understanding this correctly, it sounds like the new HIC module may require the pins to be switched back.
 
Bob, many of us can understand the sentiment of just wanting to be done. But holy cow, is this community coming to your aid! Man that has to feel good. Most of us are incapable of helping but of course we're still following along and we want you to succeed!
 
Tony references a SL . Was there another one after the previously mentioned one? (I e. The one that didn't include me)

No, you didn’t miss anything; it was never issued. This just speaks to how few owners download their ECU logs. But in their defense, spending $2k for a dongle that allows you to download them, and have no documentation from Rotax for interpreting them, doesn’t exactly encourage one to do so. But hey, the B.U.D.S. software is free 😁
 
No, you didn’t miss anything; it was never issued. This just speaks to how few owners download their ECU logs. But in their defense, spending $2k for a dongle that allows you to download them, and have no documentation from Rotax for interpreting them, doesn’t exactly encourage one to do so. But hey, the B.U.D.S. software is free 😁

I just want to mention that I have taken the IS Diagnostics course, so I have the software/license to interpret the log files. So far there are not many of us out there that can do this but this will change quickly over time.

I will be glad to review logs and share the Rotax guidance with anyone that needs help. The more opportunities I have to do this, the more I will learn.

I'm easy to find here on VAF via DM.
 
I have to admit I have no idea what pins are supposed to be where now on the maintenance port now after reading some of the posts

Are the current assignments on the KAI/electric schematics correct or no?
.

Checking that seems like the next logical step but I need an up to date reference to consult.
 
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One possibility here is the canbus wires are not pinned correctly. Take a look at SL-00009 and see if it may apply to your harness. https://www.vansaircraft.com/service-information-and-revisions/sl-00009/

Edit:
Also see this thread: https://vansairforce.net/threads/12is-b-u-d-s-connection-issue.217113/post-1689219

Latest wiring diagram versus original
View attachment 98246
We had this on our school RV-12iS, reverse the wires and the Rotax Diagnostic program worked.
 
I have to admit I have no idea what punscare supposed to be where now on the maintenance port now after reading some of the posts

Are the current assignments on the KAI/electric schematics correct or no?
.

Checking that seems like the next logical step but I need an up to date reference to consult.
This is how the maintenance port should be pinned out. When Vans switched to the 2nd version of the HIC Module they flip-floped the wiring for this on the HIC accidentally, the. when they moved to the 3rd version they corrected it but ai believe they didn't put out a 2nd service letter, so a bunch of people might have this wiring swapped without knowing it. You can get a lot of the same diagnostic info from the EFIS without the use of the BUDS software, so im guessing its gone largely unnoticed. If you put the G3X into configuration mode and select "System Information" there will be a FADEC box. With Lane A and Lane B on you can tap on that and it will have diagnostic info on the screen.
 

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Saturday morning and Josh from SteinAir is providing technical support. Amazing, but not at all surprising from the SteinAir team.
 
There's a canbus issue. He couldn't connect to the ECU for some reason . He also found that the EMS isn't working .

He said he could understand why injectors were suspect but there's something more going on somewhere. Too many things aren't working right and if I try to start the engine again, it's going to damage it

For the canbus, since BOTH your EMS (which I take to mean that the GEA24 engine monitor box isn't receiving any data from the ECU), and the Maintenance port both aren't working, then I would first jump to the possibility that Stein mixed up the wires for both of those connections. Although they are both "canbus", they are separate buses -- one is encrypted (technically just obscured) so you are forced to purchase the $2000 BUDS dongle for maintenance.. and the other is cleartext so that any engine monitor like Garmin/Dynon can read the data. The mixup would be the pins in the dsub connector at the HIC module. Or, as others have said, the Van's mixup of the two Maintenance Port pins.. which is high and which is low.. I think is playing a role here too. The BUDS dongle will see data on that port almost immediately after an Ignition Lane is turned on.

Though in your initial post from August, you were talking about EGT temperatures - which implies the G3x (and GEA24) are getting data. ? Just throwing a dart here, but what about an ECU connector that isn't fully seated, or has bent pins? Its usually an item that is set-and-forget, but since the engine has never run successfully, I suppose it could be in play too.

I too am willing to spend some time up there with you, but it sounds like you have more qualified help on the way! Please don't sell the project, we'll get it working. I still suspect that the solution is something simple, but there may be more than one issue at play which is confounding things. This is a ball of knotted wires.. but once you get on the right path to the solution, the resolutions will accelerate.
 
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And I'll just share that I helped a friend with electrical problems he was having with his new build. Turned out that out of the box, he had a defective ignition module, HIC module and transducer. Not sure the odds of something like that happening, but don't despair, as you may be subjected to something similar.
 
Anybody got an RS Flight systems IS control panel breakout box to lend him? With it can tell if its airframe or Rotax issue making the hunt much easier.
 
Just throwing a dart here, but what about an ECU connector that isn't fully seated, or has bent pins? Its usually an item that is set-and-forget, but since the engine has never run successfully, I suppose it could be in play too.
 
As I indicated, I'm completely confused about what resolution is being applied to what date.

I complied with SB00058 in December 2022. SL00009 doesn't on the surface, apply to me as my harness was shipped well after the effective date of what's covered.

Tony's comment makes mention of an upcoming SL that never came and I can't tell whether his solution is applicable only to those whose harnesses were covered under SL00009 or also includes those shipped after the effective date.

I took off the canopy and the top skin today and have checked for bent pins or loose connections. All is as it should be.

On another subject: Is there value in me buying a BUDS dongle, even though I won't be able to access the detailed information of a Level 2 person?
 
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Bob: I agree SL00009 appears not to apply, however if no data is appearing on the maintenance port for BUDS dongle connectivity then I am suspicious the port wires may be swapped. Much easier to swap on the maintenance port. Important to realize this is a data connectivity issue not a reason the engine won't run.
You indicate SB00058 was done, have you checked the compliance with SL00072? Should have microcontroller version 7.3 on board. This could effect fuel pumps and ignition. I still think your best bet is to have your Rotax tech get his hands on his breakout box to isolate the engine from airframe and download ECU data and error logs. He will be able to tell if this is an ignition issue, an injector issue, or a fuel pump pressure issue from those logs.
 
As I indicated, I'm completely confused about what resolution is being applied to what date.

I complied with SB00058 in December 2022. SL00009 doesn't on the surface, apply to me as my harness was shipped well after the effective date of what's covered.

Tony's comment makes mention of an upcoming SL that never came and I can't tell whether his solution is applicable only to those whose harnesses were covered under SL00009 or also includes those shipped after the effective date.

I took off the canopy and the top skin today and have checked for bent pins or loose connections. All is as it should be.

On another subject: Is there value in me buying a BUDS dongle, even though I won't be able to access the detailed information of a Level 2 person?

You would be better off trying to find someone that can loan you a dongle or come by and download the file. I'm surprised that the Rotax familiar person that helped you did not do this already. If you had the zip file, I would be glad to take a look at things.

I'm not confident the answer would be found in the log file, but it wouldn't hurt to look.
 
You would be better off trying to find someone that can loan you a dongle or come by and download the file. I'm surprised that the Rotax familiar person that helped you did not do this already. If you had the zip file, I would be glad to take a look at things.

I'm not confident the answer would be found in the log file, but it wouldn't hurt to look.
I have a dongle I would be happy to loan Bob.
 
You would be better off trying to find someone that can loan you a dongle or come by and download the file. I'm surprised that the Rotax familiar person that helped you did not do this already. If you had the zip file, I would be glad to take a look at things.

I'm not confident the answer would be found in the log file, but it wouldn't hurt to look.
As I understand it part of the problem is he can't get the maintenance port/ecu to talk to a dongle, thus my suggestion to use a breakout/remote panel to isolate engine from airframe wiring.
 
I have a dongle I would be happy to loan Bob.
I was reading on RotaxOwner that the dongles have to be registered to equipment to prevent people from swapping them around. Is this true. Sounds like Rotax really has their product locked down.

Another question, although I understand that the data the dongle can get from the ECU is based on the level of the user, can a log file be sent to a "higher level" expert for analysis or is what is downloaded the limited information that the mere mortals are allowed to see.

One problem I'm having is communication with the Rotax-trained person here is extremely limited and if I could just send the file to someone more available anywhere in the country, that might be a big help.
 
I was reading on RotaxOwner that the dongles have to be registered to equipment to prevent people from swapping them around. Is this true. Sounds like Rotax really has their product locked down.

Another question, although I understand that the data the dongle can get from the ECU is based on the level of the user, can a log file be sent to a "higher level" expert for analysis or is what is downloaded the limited information that the mere mortals are allowed to see.

One problem I'm having is communication with the Rotax-trained person here is extremely limited and if I could just send the file to someone more available anywhere in the country, that might be a big help.
Yes it can, but it takes a diagnosis trained tech to get into the weeds and it can take a fair amount of time as it is labor intensive. The ecu samples at least once a second, can sample more frequently.
 
Anyone can use the dongle, provided that the license key has not been lost. It is typically on a label right on the box. It's useless without the license and key that goes with the dongle but it can be passed around and used by anyone once they have downloaded the BUDS software. There is no limitation on the number of machines that a dongle license can run on.

With the dongle and the BUDS software you can extract a zip file. That zip file is read by a separate BUDS diagnostics application. The diagnostics application makes it fairly easy to separate and filter the logs items by category. It is not labor intensive and does not take much time at all. Depending on the nature of the problem and the log items, different levels of experience will be helpful. Some problems are simple once you can see the data, others are less intuitive and someone who has seen more will do a better job of interpretation. The diagnostics software does provide suggestions for many (most?) of the log items, but certainly not all of the problems that could come along. The diagnostics software does not have any kind of restrictions to run, but there is a license agreement. This is explained to IRMTs who have taken the course when the software is distributed. The diagnostics course is new so there are fewer techs with the software, but there are some of us in the wild already.

The reason I suggested earlier that borrowing the dongle may be a better focus is that the supply of dongles has been constrained. It's typically a backorder item and the distributors never seem to know when to expect more. You would probably find one to borrow before you could buy it unless you find one used. If you do find a used one make sure that you verify the license matches the dongle.

The swapped wires on the buds port is very common, and the Van's documentation seems to be kind of a loop on this issue. I have been in training sessions with the general population of A&P/IA/LSRM who are non-Van's folks, and when this comes up it's kind of a running joke. "RV-12is always have the wires swapped" along with an eye roll. If you have the master on, and ECU powered up (backup batt switch), and the dongle is not connecting then swap out the two wires in the d-sub.

One problem I'm having is communication with the Rotax-trained person here is extremely limited and if I could just send the file to someone more available anywhere in the country, that might be a big help.

I would be glad to take a look at the log file. Prior disclaimer that I'm not sure we'll see the problem there applies, but can't hurt to review.
 
Update:

Josh Swenson at SteinAir stopped by the hangar yesterday and you have to know the background to fully appreciate why he should be in the RV Hall of Fame. His toddler is sick. His wife couldn't get the day off. He had to call his dad who had to hustle out of a dentist appointment to drive to his house to take care of his son so that HE COULD DRIVE TO MY HANGAR AND HELP ME.

Hey, I suggested we postpone, but he was having none of that talk.

He went over the wiring, swapped the pins on the maintenance port, made a few configuration changes in the G3X and tidied up a few more things and proclaimed it fit for service.

We alternated between wanting to find something and not wanting to find something to account for why the 912iS is presently a brick. The best we could do -- and it's a big thing -- is get the ECU to talk to the dongle, which will happen when the Rotax guy stops by again..... someday.

Listen to me. I have said FOR YEARS that everyone should be ordering avionics from SteinAir and I've said it since Stein and Jed covered everyone with the Direct To debacle a few years ago and nothing in the intervening years has made me change my view on this.

But they should at least consider changing the name to JoshAir.
 

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Update:

Josh Swenson at SteinAir stopped by the hangar yesterday and you have to know the background to fully appreciate why he should be in the RV Hall of Fame. His toddler is sick. His wife couldn't get the day off. He had to call his dad who had to hustle out of a dentist appointment to drive to his house to take care of his son so that HE COULD DRIVE TO MY HANGAR AND HELP ME.

Hey, I suggested we postpone, but he was having none of that talk.

He went over the wiring, swapped the pins on the maintenance port, made a few configuration changes in the G3X and tidied up a few more things and proclaimed it fit for service.

We alternated between wanting to find something and not wanting to find something to account for why the 912iS is presently a brick. The best we could do -- and it's a big thing -- is get the ECU to talk to the dongle, which will happen when the Rotax guy stops by again..... someday.

Listen to me. I have said FOR YEARS that everyone should be ordering avionics from SteinAir and I've said it since Stein and Jed covered everyone with the Direct To debacle a few years ago and nothing in the intervening years has made me change my view on this.

But they should at least consider changing the name to JoshAir.

Steinair is the best!!!!!!
 
The "education" part of "for recreation and education" is continuing and I'm certainly learning a lot about the engine. I've removed the pilot side fuel rail and removed it , then removed individual injectors (I've never actually SEEN an $11 O-ring until today. Exciting!). I don't know whether there's anything in here or not. It's hard to see and the borescope gives me only fuzzy pictures.

I guess I'll clean with brake cleaner and see.
 

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That make injector cleaners and injector-cleaning solvents.

 
I know this has been WAY more than frustrating for you as it seems like every turn you take brings you to a dead-end alley. Probably everyone on this list hears a voice saying 'I hear you, buddy!' having been down such blind alleys likely more than once! Good thing C4 is not readily available or there would be more blown-up airplanes sitting in a field somewhere! :ROFLMAO: I have been there myself including a mysterious tendency for the Cub engine to just suddenly stop producing power! THAT gets one's attention!! I went through EVERYTHING to find a source and finally switched out a cylinder that checked out in every way except it was the oldest cylinder on the engine. Turned out that was the right choice: an intermittent sticking valve that eventually messed the valve seat up. No problems since. But I also have two new magnetos, a rebuilt carburetor, all new flexible fuel lines and all hard lines cleaned out, both tanks inspected, new fuel caps, screens cleaned.....I must be forgetting something........

My amazing instructor had a saying. When we would be working on something on his or my airplane and were coming up with no solutions, he would say (having never smoked a day in his life!): Well, time to go roll up a cigarette and have a smoke. His way of saying: Lets go out and take a stroll down the taxiway and think about other things. Mountains are sure pretty today...........

SO: DON'T SELL YOUR AIRPLANE!! That is the one thing you would regret! You have a HUGE number of people behind you and cheering for you and expecting good things! That Josh showed up tells you something about your support group! YOU WILL GET THIS FIGURED OUT and, once flying again, will think: There! Let's not do THAT again!!

Keep at it! We are all waiting for you to tell us about getting back in the air again!!

Your comment about the $11 "O" ring cracked me up............... :ROFLMAO: :ROFLMAO:
 
My amazing instructor had a saying. When we would be working on something on his or my airplane and were coming up with no solutions, he would say (having never smoked a day in his life!): Well, time to go roll up a cigarette and have a smoke. His way of saying: Lets go out and take a stroll down the taxiway and think about other things. Mountains are sure pretty today...........
It has always amazed me what I would see that I didn't see earlier after a 'smoke break' (and I don't smoke, never have). I would tell Service Techs that worked for me for years that would call when frustrated "go take a smoke break and come back," even when they didn't smoke. 90% of the time, they'd report back within a few minutes: "Found it!"

Don't give up! The solution is somewhere. The whole process of building isn't "Well, that was a mistake." It's usually "Well, that didn't work, what should I try next?" Everything is a process when trying to find the solution.
 
That make injector cleaners and injector-cleaning solvents.

Using brake parts cleaner
 
I was hoping to see some gunk in any of the left side injectors, but I didn't. I bought an injector connector from the auto parts store, hooked it up to a power supply, filled the injector with brake cleaner and put 35 pounds of air in it as I activated the connector, blowing out the fluid as a mist onto a shop towel. Repeated for all four injectors.

I took off the right injectors. These are the ones that allegedly work. On one there was an amount of a greasy substance pooled in a corner - O-ring lubricant? You can sort of see it in the picture. So cleaned that out.

All the Loctite, new rings and gaskets, and lubricant are due in today so perhaps tomorrow I'll start putting things back together.

OR....

I'll send all of these off to Lockwood for professional cleaning. They use an ultrasonic device with mineral spirits, according to Dean Lockwood.

It remains difficult for more to believe that four injectors were all clogged, preventing 2/4 from lighting. That would mean we have an electrical problem somewhere but so far everything checks out.

I'm awaiting a new laptop to use with the Dongle my online pals have provided. That's due on Tuesday. Perhaps the log file will be more illuminating.

I'm running out of time with knee surgery due on 11/19. No way I'll be able to get back into an RV until I'm back to normal.
 

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