Garmin G5 GAD13/GTP 59 Install Materials

[TheAv8r]

Hey all,

I've read through a few of the DIY threads on putting in the Garmin G5 GAD 13 & GTP59 OAT to display wind direction and TAS. I talked with my A&P IA doing my annual this year if he was game for doing it since we'll have the airplane apart for the annual and he kindly agreed to, as long as I bought all the parts necessary for the install. The GAD13 and GTP59 with Connector Kit is super easy to find, but I'm having a hard time putting together all the other pieces needed for the install, all the various kinds of wiring at the right Milspec, the right crimp splices, the right solder sleeves, etc. I don't understand it all, and don't want to burden my friend who's willing to dig into this project with me by asking him to go through all the manuals and put together what I need to buy. 

You think software guy would be able to understand electrical circuits, but I also know when to say I'm over my head . I've spent hours googling to try and connect the dots and am about ready to cancel the project.

To those who have done the install... what wire did you have to buy and where did you get it? What crimp splices and solder sleeves? Spruce has some, but not others... Also, what is a shield block ground referenced in the manual? A ground done with shielded wire?

Referencing the manual: https://static.garmin.com/pumac/190-01112-10_29.pdf 

The list I've come up with so far is:

 

• 16 AWG Wire

  • Pg. 99, wiring diagram

• 22 AWG Wire

  • Meets M22759/34 Spec or Equivalent (STC specifies M22759/16)

  • Pg. 99, wiring diagram

• All shielded wire shall meet M27500 Spec or equivalent using M22759/34 (STC specifies M22759/16)

• 4 - W/B/O shielded twisted wire 3 conductors

  • Pg. 99, wiring diagram

  • https://www.prowireusa.com/p-574-22-awg-x-3-shielded-cable.html 

• 3 Crimp splice AS81824/1-1

  • Pg. 99, wiring diagram

• 4 solder sleeve splice

  • Pg. 99, wiring diagram

• 18-22 gauge terminals

• 1/16th Flat Braid (AA59569F36T0062)

  • Pg. 74, Connector Parts

  • https://www.aircraftspruce.com/catalog/pnpages/11-17498.php 

• MS25036-149 Terminal lug (ring style)

  • Pg. 74, Connector Parts

  • https://www.aircraftspruce.com/catalog/elpages/insulterms.php?clickkey=6711973 

    • 22AWG, stud-size 8

• Screw, PHP, 8-32 x 0.312", Cad-Plated Steel, or Screw, PHP, 8-32 x 0.312", Stainless MS35206-242, or MS51957-42 12 Split Washer, #8 (0.045" compressed thickness), Cad-plated Steel, or Split Washer, #8 (0.045" compressed thickness), Stainless MS35338-42, or MS35338-137 13 Flat washer, Cad-plated Steel, #8, 0.032" thick, 0.174" ID, 0.375" OD, or Flat Washer, Stainless, #8, 0.032" thick, 0.174" ID, 0.375" OD NAS1149FN832P, or NAS1149CN832R

  • Pg. 74, Connector Parts

• Shield termination AS83519/1-X (SAE-AS83519)

  • Pg. 74, Connector Parts

• Extra D-Sub pins

[OR75]

parts is not the complicated part.

pulling wires ( probe in the wing to instrument / circuit breaker connection / etc ...) will be  

[McMooney]

I purchased ALL parts from Aircraft Spruce or Dallas Avionics, be prepared, that canbus wire is some expensive stuff.

simple wiring however , canbus is only 2 wires, daisy chained from component to component.  you will need good deal of power and ground wire, probably 22awg unshielded.

if you can't borrow the correct crimpers be prepared for a sticker shock, those suckers are EXPENSIVE.

 

Avionics, Install Supplies, Pilot Supplies, Avionics Test Equipment (dallasavionics.com)

 

where are you btw, i can check if i have some leftovers

Edited May 9, 2023 by McMooney

[Vance Harral]

I highly recommend SteinAir for supplies: http://steinair.com.  They have videos that show how this stuff wires together: https://www.steinair.com/support/videos/

Among other supplies, they have a reasonably priced pin crimping tool: https://www.steinair.com/product/4-way-indent-crimper/.  Others may pooh-pooh this particular crimper as "cheap", but it got the job done for us with no trouble and our installation has been reliable so far.  My recollection is that the GAD13 requires only the low-density pins, but for an extra couple of sawbucks you can get the high density insert as well.  They also have a nice, inexpensive ratcheting lug crimper: you'll want both of https://www.steinair.com/product/ratcheting-crimper-frame-only/ and https://www.steinair.com/product/insulated-terminal-die-only/ if you need this.  Don't use a non-ratcheting hand crimper for this job!

Regarding wiring, the 22AWG M22759 unshielded for this job is just for power/ground, so you probably don't need much.  But it's inexpensive, so you can get a dozen feet or so of each and have plenty to spare.  I like red for power, black for ground, and white for signal, but there is not really an "aviation wiring color code" to follow, and many installers just use white for everything.  The M27500 is "inexpensive" shielded twisted pair, and is only needed if you need more than a 10' run from the OAT probe to the GAD 13, because the OAT probe already comes with 10' of shielded twisted pair wiring.  The CANBUS wire is expensive, but you hopefully only need a short section to run from the GAD13 to the nearest adjacent G5 or GAD device.  Frankly, you can get away with using M27500 for that run, but most people pony up for the CANBUS wire.  Also, while I am not discouraging you from following the Garmin wiring diagram to the exact letter, most modern installations I'm familiar with do not run independent shield termination with 16AWG and/or braid as indicated in the wiring diagram.  Instead, they use pre-fabricated solder sleeves with pigtail connections, see https://www.steinair.com/product/14-solder-sleeve-wpigtai/.  Suggest buying a handful of these in both the 1/4" and 1/8" sizes.  You do, in fact, need small gauge solder sleeves *or* crimps to make the "daisy chain" connection for the CANBUS wiring from the nearest G5/GAD device to the GAD13.  Buy extra and be careful, as amateurs (like myself) tend to screw it up the first time.  Same thing with the ring terminals: they are inexpensive, so buy extra.

Highly recommend you purchase a "de-pinning" tool, in case you make a mistake pinning the connectors.  Again, these come in both low- and high-density sizes: https://www.steinair.com/product/insertionremoval-tool-for-larger-type-pins-mil-spec/ and https://www.steinair.com/product/insertionremoval-tool-for-high-density-d-sub-pins-mil-spec/, respectively.  I think you only need low density.

I know I've put a lot of SteinAir links above, but I'm not trying to shill for them, necessarily.  I am testifying that we used their parts and supplies for our own DIY installation and found everything to be of good quality.

 

[Vance Harral]

14 hours ago, TheAv8r said:

Also, what is a shield block ground referenced in the manual? A ground done with shielded wire?

It's the connection from the "shield" wire inside a shielded, twisted pair, to the "block" (usually the connector frame) of the device the shielded wire connects to.  See the linked video below:

 

[EricJ]

For avionics supplies like wire, connectors, tubing, etc., in addition to steinair there is:

www.glenair.com

www.edmo.com

Edmo is a go-to vendor for a lot of avionics installation and maintenance stuff.

That said, a lot of it can be obtained on amazon or elsewhere as well for much less $$.   Electrical stuff is generally so standardized that you really don't need to pay the "aviation" markup.

[TheAv8r]

Wow, @Vance Harral that was incredibly helpful, thank you for breaking everything down that way and with links to SteinAir! I know I must seem like a neanderthal asking questions like this, but I was getting lost in all the crimp splices and trying to trace by the p/n Garmin provides always led me to a different website.

[Vance Harral]

35 minutes ago, TheAv8r said:

I know I must seem like a neanderthal asking questions like this, but I was getting lost in all the crimp splices and trying to trace by the p/n Garmin provides always led me to a different website.

Don't apologize.  I have a master's degree in electrical engineering and about 30 years' experience in the electronics industry, and I went through exactly the same process.  Building avionics wiring harnesses is not especially delicate or complicated, but like anything else you've never done before, there is a learning curve the first time.  The difference between you and others is that you're actually trying to read the installation manual and follow exactly what it says.  Once you've done your own, start looking at field installations done in other airplanes, and you'll soon discover that many of them are done poorly/incorrectly, and yet still "work".

[rbp]

a cautionary tale: I had a new plane which developed a starting problem. Sometimes it would start, sometimes it would take a few tries to start. twice had AOGs, and then wouldn't start at all. they tested, repaired, replaced everything over the course of a few months. it turned out to be a bad crimp in the connector block that went to the panel with the start button.  it was arcing whenever the button was pressed, and eventually the gap became wide enough that it would no longer start. 

[McMooney]

so after checking my after install bag, I noticed the installer didn't use ANY of my prefab professionally made harness, seems my original fabricator made it about 2 or 3 feet 2 short and instead of extending it the new installer  just removed the connectors and  rewired.    Even the pins are still in place.

 

we can probably come to a deal if you're interested.

I've included pictures of the harness before the ends were removed.

 

 

 

 

[TheAv8r]

14 hours ago, McMooney said:

so after checking my after install bag, I noticed the installer didn't use ANY of my prefab professionally made harness, seems my original fabricator made it about 2 or 3 feet 2 short and instead of extending it the new installer  just removed the connectors and  rewired.    Even the pins are still in place.

 

we can probably come to a deal if you're interested.

I've included pictures of the harness before the ends were removed.

 

 

 

 

Oh shoot, I already ordered all the new parts yesterday. Thank you for going out and checking! The kit comes with pre-fab leads, but we'll likely have to extend since it has to go all the way down the wing and back through the fuselage to where the GAD 29 is. I think we're set for now, but if we end up hitting a blocker, I will definitely let you know and we can see if we can figure something out.