Lane A and B generator failure on 2nd flight

I did my first flight on February 6th. Before that I accumulated 1 hour on the engine in testing, working the brakes and swinging the compass.
After a few weeks of poor weather I planned a second flight three weeks ago. Immediately after starting the engine, both lane lights started blinking. And afterwards Skyviews error read-out showed "generator failure".

I bought a dongle and borrowed a simulator. Today, running the engine with the simulator the error was confirmed. Rotax is looking into it, and I am waiting for their input. But I thought in the mean time I might ask if anybody on the forum has any experience with this. Any suggestions in finding the origin of the error are much appreciated.

Can't see any photos!

rolick22 said:

Can't see any photos!

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I see them with the Chrome browser but not the Edge browser.

See if you have any error lights in the Rotax engine fuse box. Look through the clear window on the fuse box cover which is on the left upper firewall under the cowl.

I have a ULS, so my comments should be taken with a grain of salt. Wouldn?t you have a negative battery load indication if the generator really went Tango Uniform (technical term)?

Thanks for your suggestions. I understand little of the electrical design of the iS and I am very happy with any input.

Deene, all lights in the fuse box are in the green (with the engine not running).

Rich, you may be right that the generators went south. But if I understand correctly there are at least two of them. So I was hoping that this problem might be caused by a loose connection or cable. But I have no clue where to start looking.

I hope the pictures are visible now.

Lane a and b

My problems with the wiring connectors on my RV 12 ULS Rotax were numerous. The engine started with the MAGS ? OFF ! Luckly the AC was chocked, over crimped connectors cut the grounding wires, Other pins pulled out with very little pressure. I don't know who is to blame, electrical harness contractors or Rotax. May not be your prob but it was certinally was mine!!! Hope this helps other folks! GL Ben

Red Lights on Both Lanes

I own an RV12-iS ELSA, bought with 17 hours on it last September (all Garmin gear). In November, at run up, one lane light was solid red, and one blinking. Appeared that second generator not active. I taxied back to the ramp, shut down, waited five minutes, and started her up. No issues. Have made about 18 flights since then without a problem.

During the lane check, I may have turned off Lane A, turned it back on, then failed to wait for the red light to extinguish before turning off Lane B. Maybe. Since then I've been careful to not do that. I have no idea if what I did had any impact.

We had a vexing failure on the 12is that was recently completed by the Tango program. The signature was an intermittent low voltage and battery discharge warning from a possibly failing generator B. In this case, a B generator failure does not cause a lane B fail light indication

After major debug effort with excellent support from Vans and Leading Edge Airfoils, I found an intermittent pin on one of the connectors on a cable from the Rotax fuse box to the HIC module behind the instrument panel. This caused intermittent operation of the B generator regulator.

Since this was a prefabricated cable supplied with the RV12iS kit, you should carefully examine the connectors on the cables to the HIC. In our case one pin would not stay seated which cause the intermittent failure.

We replaced the pin on the wire and carefully installed it in the connector shell and all was well...

Hi Deene, that is very helpful!!

Was it one of these connectors? On the AV-60009?

Yes, also called the ?HIC? or Harness InterConnect module. Check pins by inspection on all four cable connectors.

I checked all four connectors today. Every pin and wire. They were OK as far as I could see.
It is perhaps of interest that not one, but both lanes have this problem. And not on and off intermittently, but rock solid immediately after starting the engine.

The dongle that I bought worked fine with Rotax' simulator. But I cannot get it to connect with my maintenance port. No signs of life. The maintenance port (also) interfaces with the Harness Interconnect module. Maybe there is something wrong with the module. I discussed that today with Vans support and they will check with their expert(s).

Maintenance Port Wiring

The wiring in my port was wrong. The two wires had to be reversed. Check with Vans, but that was my issue.

Hi John, thanks! Vans also suggested to check and try reversing the two wires of the maintenance port.
I tried this morning. The wires were inserted OK. Then I reversed them. But it didn't work in either way. Not even a flicker of the steady dongle light. Afterwards I reversed them back to their original postion.

After starting you have to go to 2,500 for a few seconds and then slow down to 2,000. That is for the K1/K2 relay to switch power from the generator B to the main bus and generator A to the engine computers. I deleted my previous message with the log file and will post a better example of a SV log.

Here is a typical example of what happens in the log files (from Dynon) 50 sec after starting the engine. The amps change from + into -. Subsequently errors appear and information disappears while the engine is still running. I am not smart enough to interpret these data, but perhaps one of you can.

files or Jpg's not visible. If you are getting positive charge and voltage over 13.7V after starting, it's not your alternator or generator, it's something else.

Niner/Randy thanks for your input.

Rotax asked me to check the continuity between the regulator A, B, and aircraft ground(s). I did. The regulator A ground is connected with the EMS ground and not connected with B, and B connected with the aircraft ground.

I also checked the ground of the starter relay. It is grounded to the firewall, and not to the EMS ground. Rotax thinks that this might cause the error. See this page 5 from the IM 80-00-00 and 6 from 24-00-00. I will check with Vans support.

So it appears you need to run a ground wire or "earth" wire, as the Brits call it, to your starter solenoid, yet keep starter solenoid isolated from ground with rest of plane. Is there a specific part on the Rotax starter solenoid or case, that does that, which might be missing?

Yes. Rotax' ground starter relay wire is still available, but cut, heat schrunk, and not in use. With the relay grounded to the firewall (46iS-09).

I wouldn't know how to mount the relay to the firewall, keep it isolated and use one of the bolts to attach the ground wire, all at the same time. And perhaps that was also the designers problem.

Although I would be delighted, it still remains to be seen if changing this setup will solve the lane error problem.

Jeroen,
I am sorry you are having this problem with your brand new airplane. I am sure it is frustrating.

I have avoided commenting in this thread because there has already been a lot of incorrect information being bounced around and in that situation it becomes very hard to keep troubleshooting on track using this type of communication, so I avoided adding to the problem.
The erroneous info is probably based on incorrectly applying general knowledge of typical 12 V charging systems; and no knowledge of the RV-12iS power generation system.

Note that I didn't say charging system because the system used by the 912iS is much more than that. It is actually two independent power generation systems that can be used to selectively provide power to the electrical engine dependent systems or charge the airframe battery. The dual engine ECU's have control over how this distribution is handled, with the pilot still in the loop with the ability to manually connect the engine systems to the airframe battery using a back-up power switch if in the extremely unlikely even both charging systems have failed.

I understand that the wiring of the start relay is in conflict with what you found in the Rotax documentation, but I offer this fact.
Every RV-12iS built so far has had the relay installed and wired the way yours is. That includes the first prototype, approx. a dozen SLSA production aircraft, and all of the customer built aircraft completed so far (I think at least 15 - 20 but I don't know for sure). Yours is the first airplane I am aware of to exhibit this problem.

This makes me highly doubtful that your issue is caused by the body of the start relay being connected to airframe ground. Another thing that I think makes it highly unlikely is that it sounds like you have ~ 2 hrs of normal systems operation prior to the problem occurring. That makes it highly unlikely that the relay installation is causing the problem.

There has been very few engine/electrical problems with new RV-12iS' but those that have occurred have been prominently related to issues with the wiring and connections at the AV-60009 HIC module. My recommendation would be that you take another very close look at all of the wiring and connectors related to it, along with looking through the KAI and double checking any wire terminations / insertions that had to be completed by you during the airplane build.

Another thing to confirm is whether inspections prescribed by SB 19-08-16, and SB 20-03-16 have been complied with. I don't think the issue addressed by either of these would have any influence towards your issue, but I can't even begin to count the number of times I thought that and was wrong so it would be good to confirm.

Scott,
Thanks for your update and explanation. It is good to hear that the relay ground thing is not likely to be causing this problem.

I complied with the SB?s and I will check the connectors of the HIC module again. Check the Ignition module connectors and go over all the wires that I had a hand in during installation.

In an earlier post I mentioned that downloading the ECU log files went smoothly with the Cockpit simulator and my dongle (as in 76-10-00). But that I could not get it to work with the maintenance port. Whatever I did. What do you think, might that have anything to do with this error?

Thanks for your help.

jcboon said:

What do you think, might that have anything to do with this error?

Click to expand...

Some of the earlier harnesses had the xmit and receive serial data wires inadvertently reversed on the engine maint. port. When a port is not functioning, swapping the two wire positions has always resolved the problem so I am not sure why it is not working on yours.
Is there any chance that when you reversed them you inadvertently inserted one into the wrong pin location? It is easy to get turned backwards on the pin positions depending on which side is being looked at.

Sorry, I don't have enough familiarity with the electrical systems of the engine yet to make a judgment on whether the the maint. port not functioning might be connected with the Lane warning light problem, but with what I have learned so far, it doesn't seem like it would.

Hi Scott, thanks for the update.

Below a picture of the maintenance port as tested with the dongle.

Last year we were instructed to remove the seal pins from the HIC B connector. I cannot remember if I tried to install the HIC connector before removing those pins. If so, could I have damaged the HIC module that way?

Next week I will go to the airport and check wires and connectors.

Hi Scott,

you were right about the connectors. I found a poorly seated pin in the ignition/starter D-sub connector.
No more errors after starting the engine, and no more blinking of the Lane A and B lights. Problem solved.

Thanks for your help.

P.S. Even one loose D-sub connector pin has unpleasant consequences. Maybe it should be seriously considered to "pull" check each and every connector pin before installing the main wiring harnass as in chapter 42.

Bad news. After the engine had a good night's rest, the error is back.

I sent the logdata to Rotax and wait for their suggestions.

deene said:

We had a vexing failure on the 12is that was recently completed by the Tango program. The signature was an intermittent low voltage and battery discharge warning from a possibly failing generator B. In this case, a B generator failure does not cause a lane B fail light indication

After major debug effort with excellent support from Vans and Leading Edge Airfoils, I found an intermittent pin on one of the connectors on a cable from the Rotax fuse box to the HIC module behind the instrument panel. This caused intermittent operation of the B generator regulator.

Since this was a prefabricated cable supplied with the RV12iS kit, you should carefully examine the connectors on the cables to the HIC. In our case one pin would not stay seated which cause the intermittent failure.

We replaced the pin on the wire and carefully installed it in the connector shell and all was well...

Click to expand...

This started happening recently on my RV12-iS with 55 hours. Sounds similar. Battery showing -2 amps when steady landing lights are on in flight. On final last flight, right after turning lights on, got a ?battery amps? annunciation briefly till I added a bit of power.

1. Start engine, go to 2500 RPMs till battery amp indicator goes from negative to +11?so far so good.
2. Turn on steady landing lights and see the +11 change to +9. Turn off landing lights.
3. In flight, battery amp indicator typically shows 0.
4. Turn on landing lights in flight, and see battery amps show -2. Turn landing lights off.
5. On final, turn on lights, and get a ?battery amps? annunciation on screen briefly till I add a touch of power.

The dongle that I bought together with a friend works fine with the Cockpit Simulator from Rotax in downloading ECU log files.

But we cannot get it to work with the maintenance port. Neither with my or his RV-12iS.

There is not much space on the D-sub connector as mounted in the panel, for the dongle to make a good connection. But also after disconnecting the maintenance port connector from the panel, we didn't get it to work with the dongle.

Are any of you having the same or better experiences with the dongle and the maintenance port on the RV12-iS?

Update: I just learned from the mother ship that the wires should be blue/white at 7 and white at 2.

YES!! Sorted.

With the help from Vans support, guiding me in the right direction, the dongle works after swapping the maintenance port wires. And I found a partly disconnected fuse in the fuse box.

The engine runs like a charm again.

Thanks for your help and support!!



After:

Glad you have it working again. Have fun flying now!