Skyview conversion harness

Hi, I am one of those that did the wiring form the D180 Flight Deck and then waited for the Skyview conversion. This is based on the early 08-25-11 wiring kit that came without the harness for the pilot and co/pilot to connect to the AV5000. I made my own and have been trouble shooting it on and off for about 5 months. The major problem was that in the isolate position on the 403 intercom the radio reception was not usable, in the intercom position the radio transmissions were too weak to be useable. I also had a bad co/pilot head phone jack, some times intermittent some times open, I gave it the foot treatment and replaced it. The main problem remained, why the difference in radio reception between intercom and isolate?
Everything with the wiring and the schematics checks out OK.
The problem that I finally found yesterday was the there is a discrepancy between the wiring in the WH 00036 conversion harness. The wire on pin # 3 that goes in the conversion harness as pilot PTT comes out on pin #3 at the AV5000 labeled as co/pilot PTT. The co/pilot PTT wire on pin# 2 also changes it's name at the AV5000 to pilot on pin #1. I swapped pins #1 & 3 at the AV5000 d-sub and all problems are now gone! Van's was not aware of this wire switch and they will correct the wiring diagram. An easy check to see if you have this problem switch the intercom to isolate and try transmitting from the co/pilot side and/or see if your radio signal gets very weak on the pilot side when switching between intercom and isolate.
I still have some hair left, but not much!
HTH, Henry

Is it possible that the Intercom DIP switches are also part of this situation? See page 14 of the FlightCom Installation Manual for a discussion.

I lose sidetone when in the ISO position, so maybe I have the switched wires, or have the DIP switches incorrectly set, or both. In any event, I don't operate in ISO and everything is working (as well as that Intercom works, that is, which is not very well IMHO.)

Bob Bogash
N737G

Bob, I did check the dip switches and put them back to the factory setting. I purchased another 403 from Flightcom as I was sure that the original one had a problem even though Flightcom had checked it out and blessed it. It sounds like you have the same symptoms that I had. If the radio volume drops drastically when you switch between Iso & Intercom and you can transmit from the co/pilot side when in Iso swap out pins #1 & 3 on the d-sub that plugs into the AV5000 and it will most likely all clear up. Look at the wiring diagram for the conversion harness, the pilot and co/pilot wires change names between in and out. Like you, I thought that the 403 was a poor intercom but when it is wired correctly it isn't too bad. Just wish it hadn't taken me 4 months to find it!
Henry

I'll put it on my To-Do List for the next time that instrument panel cover gets removed - I just removed and reinstalled it to work back there. It's been removed and reinstalled so many times now, it needs a new paint job.

My main gripe with the Intercom is that the Squelch Control has about 300 degrees of travel, but only one miniscule "sweet spot." I am always playing with it before start up and then in-flight to try and keep it in the sweet spot - hard to do while flying in bumpy air. A fraction either side of the sweet spot either shuts down the I/C altogether with your passenger, or opens it up to all the engine and air noise.

Thanks for your diligent research on this - you have a lot of persistence.

Bob Bogash
N737G

Henry, I did the check - and, YES - I have the problem. I plan to open that instrument cover one more time and swap those misdirected wires. I would assume everybody with that WH 00036 wiring harness must have the same problem. A lot of them might not realize it.

I think I spent about 4 months of build time studying and re-studying that wiring diagram until my eyeballs hurt, and eventually tracing almost every wire. But not those wires. It's insidious - it works,.... but it doesn't work right!

Thanks again for sticking to this one and finally nailing it. It's a real hair-puller.....

Bob Bogash
N737G

Henry - finally got around to putting my airplane down for maintenance and did the pins 1 and 3 swap per your info.

Worked like a charm - I can now flip the intercom to Iso and be able to use it from the LH side as intended.

Good work. Vans should publish a note describing the error so people can make the correction.

Bob Bogash
N737G

well, I have intercom problems. Going to ISOLATE cuts off the pilot side from hearing the radio. I swapped 1 and 3 and the result was very poor transmission - actually had to use the right side headset and xmit switch, and no Fix on the isolate problem. So my pins 1-3 were OK. Swapped them back. Intend to troubleshoot more this winter. Problem is the plane is at my home hangar and cannot receive any ATIS/AWOS signal for the troubleshooting! I have a handheld but that will be clumsy for testing...

Your problem is really puzzling, Bill. As Henry dug out, the two wires are swapped on the wiring diagram and so Stein fab'd the harnesses per the drawing. I was able to confirm that going to ISO worked on the co-pilot side, and when I swapped the wires, it moved over to the left where it belonged.

I did an ATIS and radio check and all was good.

Are you working with the Conversion harnesses? - the ones for folks who had the D-180 wiring installed but then went with Skyview?

Bob Bogash
N737G

Bill H,
If the ONLY problem is that isolate disconnects the pilot's headphones from the aircraft radio (and NOT the copilot's), then here is something to try:
On the back of the intercom, swap the wires going to pins 9 & 11, and swap wires going to pins 10 & 12.
Joe Gores

Mich48041 said:

Bill H,
If the ONLY problem is that isolate disconnects the pilot's headphones from the aircraft radio (and NOT the copilot's), then here is something to try:
On the back of the intercom, swap the wires going to pins 9 & 11, and swap wires going to pins 10 & 12.
Joe Gores

Click to expand...

This man is a genius, this makes entirely too much sense, guarantee it will work!

I am working with the Skyview conversion harnesses - the first ones sent out. I intended to dig out the book and figure out the intercom pinouts and solve the problem there rather than upstream of that!

Why? For example, when I connected my new ADSB box to the AV5000A (like many others have done) the power and ground worked but the TX-RX connection did not work. After continuity checks confirmed, I had to run those wires directly into the EFIS plug on the back of the Skyview, and bypass the AV5000A. So Im not really trusting the wiring diagrams or my AV5000 box for that matter...

I really began troubleshooting earlier in the year when I could not make Halo headsets work in the plane! Other headsets work fine and the halos work in other planes. Other stuff has prevented me working further on that, set them aside for the winter with less to do.

And here's a weird thing. I did the annual inspection. During that I did the gear mod and installed the ADSB box. The ADSB is behind the aft bulkhead and the ADSB antenna is about 3 feet back from that bulkhead. I also connected the new RX wire from the comm radio to the Skyview for push-pull frequency - works fine. No other changes!

Well, since doing all this, I often (not always) get loud squeally-howly feedback in the headset when I transmit on the ground (like before takeoff). Not when in the air. Not a squelch kind of thing.

??? ??? ???
Bill