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Wiring Harness Woes

asw20c

Well Known Member
Today I cleaned up the WH-00057 aft fuselage wiring harness installation as seen on page 10-25. Not sure how others managed, but I found that some of the wires (specifically C723, C1038, and C1039) that run between the C409P and C410P molex connectors were too long by about 8-10 inches compared to all the other wires. I ran the wiring harness exactly as depicted in the plans, yet the C1036 and C1037 white wires were barely long enough to extend forward of the F-01406 bulkhead, and that the previously mentioned three wires were too long so I had to have them double back on themselves along the bellcrank ribs to make a neat looking installation. Anyone else have a problem with this wiring harness? Otherwise I have been very impressed with the quality of the antenna and rudder cables that have been provided in the kit.
Also I'm wondering what other people might have done to mitigate or prevent any chafing of the two wiring harnesses that get sandwiched between the F-01407 and F-01408 bulkheads and side skins.
 
Yep

I had the exact same situation. I too doubled the long wires back onto themselves, however, I do not plan to leave it that way. Once I'm doing the final fuselage wiring I'll shorten those wires to the proper length.

To prevent chafing in the tight spots I wrapped the wires in wire loom purchased at a local automotive parts store.

Cheers,

Greg
 
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As I have posted in the past, after chasing my tail fixing an RV-14 wiring that used the provided wiring kit I would have saved a lot of time and ended up with a better install if I just scrapped it and started over.

I'm sure I'll get flamed, but I recommend just wiring the plane like you want, and look beyond what someone else thinks is a good idea (like the wiring kit). Consider standard practices like using conduit in the tail instead of tie wrapping wire to aluminum. Another example is there is no practical reason to have the big molex connectors at the baggage compartment aft bulkhead.

Whatever you do, immediately cut off the tiny trim servo connectors and throw them away.

Carl
 
Same

I had the same issue. So, after running all the wires and temporarily tie-wrapping in place, I cut those two long wires at the C410 molex plug to match the lengths of the other wires. The pins on the larger molex plugs are easier to work with than the tiny ones on those micro plugs that you probably had the pleasure of working with on the elevator trim servo connectors:)
The two short white wires are the power wires for the elevator trim servo. I removed those completely and replaced with longer lengths that will hopefully make it to their final termination points (wherever that is), and avoid the connector at the fuselage bulkhead.
Carl may be correct about getting a cleaner install if you avoid using the kit wire harnesses and run the wiring yourself. However, for less experienced builders (me), who don't quite have the "big picture" yet, the pre-done harnesses make things much simpler. Maybe as I get more experience, I will "modify" the kit harnesses here and there to clean things up a bit.
 
I was in the same boat tonight. Trying to figure out how to run the empennage wiring took a lot of time. It just didn't make sense, especially with those longer wires. In the end, just muddling thru it was what it took. I am also in the camp of wiring it as per plans and included components and may or may not rework it down the road.
 
I just based everything on the two white wires, ended up making a loop in the bundle on the left side of the battery angles and securing with cable tie mount epoxied to the bottom skin. Seems pretty secure and keeps wires clear of the rudder cables. I can always trim these back and re-mount into the molex connector.

I ran some extra wires (red/white/black, 3-wire shielded) from the tail (behind aft-most bulkhead) along the right J-channel with enough length to reach all the way to panel in case I need them for anything, but I'm planning to use factory harnesses and modify as needed - including getting rid of as many micro molex connectors as possible.
 
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Biggest frustration I have and I haven't sorted it yet is the connector run through to the control sticks. As I've mentioned before the mini molex connectors should be left off until the wires are run. I notched the bulkheads prior to installing them but the wire is stiff, the plug is bulky and the space is limited. A 10 minute job is starting to give me bad dreams.
 
I found the plans were not that clear but after looking through some builders sites I found what I needed to know :)
For protection I used spiral wrap and expandable sheathing
 
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Biggest frustration I have and I haven't sorted it yet is the connector run through to the control sticks. As I've mentioned before the mini molex connectors should be left off until the wires are run. I notched the bulkheads prior to installing them but the wire is stiff, the plug is bulky and the space is limited. A 10 minute job is starting to give me bad dreams.

It doesn't help that the wires are too short at least in my harness and at least one other I know of. They reach the sockets for the stick connector but zero slack like it needs to keep any tension off the connector and wires. I'm still deciding how to get another few inches so I can have some slack in the wires as depicted.
 
It doesn't help that the wires are too short at least in my harness and at least one other I know of. They reach the sockets for the stick connector but zero slack like it needs to keep any tension off the connector and wires. I'm still deciding how to get another few inches so I can have some slack in the wires as depicted.

Dimension changes where made to the harness drawing quite a while ago to correct this, but unfortunately there are a few harnesses in the field that are slightly too short.
Any harness other than the very early ones will have proper length wires.
 
My stick wires are at least 6" too short and even then there would not be a lot of freedom of movement. The main wire bundles that extend up to the panel may be long enough to reach the centre avionics but there certainly will not be enough to reach switches and breakers. Thus more connections and future potential failure points will be required. The small molex connectors are not user friendly and it would be much better to use D-sub type connectors for them.
The wiring harness is to me, the only little black cloud in the whole kit.
To end on a good note; the wiring harness diagram is available from the website and I was able to get a local printer to print it full size, 3' by 4', and with the labels on the wire ends tracking down issues should be easier.
 
Dimension changes where made to the harness drawing quite a while ago to correct this, but unfortunately there are a few harnesses in the field that are slightly too short.
Any harness other than the very early ones will have proper length wires.

Scott, I'm glad changes were made but are there any plans to help those of us who purchased defective (too short wires are a defect) $1500 wiring harnesses ? So far, my kit has been amazing but this is a big disappointment.
 
wire harness with bag labelled WH-00057 "R2"

I ran into the short wire (C1036 & 37) problem when I installed my wire harness (bag labelled WH-00057 "R2") with the C410P connector plugged into the F-01406B Bulkhead and then pulled the harness aft towards the F-01412 Bulkhead.

However, if I taped the C409P connector to the F-01412 Bulkhead and pulled the harness forward towards the F-01406B Bulkhead I ended up with almost 2 inches of wires (C1036 & 37) extending past the F-01406B Bulkhead! Wires (C723, 1038 & 39) end up too long by a few inches and need to be looped.

Since my harness is labeled "R2", is this one of the newer harnesses?

Do others with the issue also have the "R2" harness?

Richard
 
Since we've gotten a few calls directly about this in the past week or so, I thought I'd just put this information out there. We have made/tested and now stock sets (co-pilot and pilot) prefabricated stick extension harnesses of 6" in length to plug into your RV-14 harness should you want them. Call us and we'll send you a set!

Cheers,
Stein
 
...I ran the wiring harness exactly as depicted in the plans, yet the C1036 and C1037 white wires were barely long enough to extend forward of the F-01406 bulkhead...

I'm resurrecting this thread as I'm at this stage of my build (page 10-25) and have the same issue. The two white wires (C1036 and C1037) are barely long enough (maybe 2"-3") to extend past the F-01406 bulkhead.

Can anybody tell me if this will be long enough? I'm not sure where or when they get connected to something else.

These are the wires I'm referring to:
 

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Depends

WH-00125 was modified by Stein half way through the process to lengthen certain wires running aft. I assume you are asking about this harness ? I don’t know when the harness was changed. I had to lengthen several wires that ran aft. Also added return grounds and twisted pairs to hi amperage device draws. (Heated pitot tube for one). WH00125 is 95% complete, not 100% depending when you purchased it. I found it better than building from scratch but other builders did not think it was worth it. Good luck !!
 
Using a Garmin autopilot?

Mine were also too short. If you are using a Garmin autopilot those two wires will connect to the pitch servo wiring harness. I plugged them into a two-pin Molex and connected the trim wires from the servo harness to the mating connector. Did this instead of running the wires out to the bulkhead connector then back to the servo (which they wouldn't reach anyway).
 
Biggest frustration I have and I haven't sorted it yet is the connector run through to the control sticks. As I've mentioned before the mini molex connectors should be left off until the wires are run. I notched the bulkheads prior to installing them but the wire is stiff, the plug is bulky and the space is limited. A 10 minute job is starting to give me bad dreams.

I feel your pain with this job. if I had it to do over again I would cut the connector off and rewire it with dsubs and shrink tubing. Super frustrating getting that molex connector over to the sticks….:mad:
 
As stated above: cut off the plug to easily run the wires. Then, get the extension Steinair makes with a new plug already installed. Use d-subs to connect the harness to the extension. An even better solution is to eliminate the mini molex plugs from the stick and the harness and connect everything with d-subs and heat shrink. :cool:
 
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