2017 G21 Pa4A - Stereo Booting

[gadgetwiz]

Help.

TLDR: Need wiring from back of LINC to Polk extension cable. 2021 G21 and PA4A Head Unit.

I have a 2017 G21 with a Polk PA4A head unit. A few weeks ago, the LINC stopped being able to control the head unit. It just says "Stereo Booting". The Polk Commander and wired transom remote seems to work though. I took it in for service, and they have replaced the Polk Head Unit, the extension cable, the Y-Adapters, AND the LINC Panoray screen.

It still doesn't work, although it apparently worked for them at some point.

Anyways, I figured the only thing left was the 4 pin DIN to the back of the LINC screen. I was particularly interested in the splices made at the factory. Unfortunately, as I was stripping back the heat shrink, the two wires separated and I don't know which color goes to which color. After looking at the wires, I'm pretty convinced that this is where the problem was, but I don't want to risk making a wrong connection. I even put an oscilloscope on it, and I'm not seeing anything useful.

I've contacted Nautique (voicemail) and Polk (pretty useless), so really need help from the community. Does anybody have a schematic or wiring diagram of this section?

[gadgetwiz]

For posterity, here is the female side (reverse for the male plug).

In my case, this meant this:
Radio ---> LINC
Black -> Blue (data)
Orange -> Red (12v)
White -> Black (GND)

YMMV. I spent a lot of time with an oscilloscope trying to confirm the wires before hooked them back up.

It did, indeed fix the problem I was having with 'Stereo Booting'.

[Scooter G]

Interesting problem, interesting solve. Not sure how you ended up at the factory splices of the 4 pin at the Linc. Good hunch, luck, or hmm that doesn't look right?
But if you figured out "the I forgot to take a picture before I cut the wires" (none of us have ever done that) using an O-Scope, you obviously have some inherent skills.
Good find, good write up. If you had this problem with a bad splice, someone else will for sure.

I love how sometimes white is coded for ground, and black is something totally different all together. It must be an engineered internationally with a domestic plug in mix, or maybe engineers just messing with our minds (engineer humor).

[gadgetwiz]

I ended up at the splice because:

• The dealer changed the stereo.
• The dealer replaced the LINC system.
• The transom wired remote never stopped working.
• I bypassed everything else by running a Polk mini-dim cable I bought from Amazon straight to the stereo.

There was nothing else left.

As far as the color coding, it's nobody's fault really. Nautique opted to use a pre-assembled mini-dim cable. They cut the plug off it and wired it to the harness with some jumper wires. Nobody chooses color schemes from those pre-assembled wires knowing what the final use-case is going to be, so the colors would be mostly random. The jumper wires made sense though. Red, Black, and Blue. The hardest part was finding the pinout from Polk.

I really don't know why Nautique doesn't have a wiring diagram for the '17 G (or at least a pinout from the LINC system available). Would have saved me a ton of time. I've been under there enough times, I could almost come up with one at this point though, and I might do that if I get under there again.