I have a HDS 8 gen 1 and a HDS 10 gen 2 touch that I bought used and did not get owners/users guide with either. My question is about the power connector. One is blue and one is red. There are three (3) wires in each, red,black and yellow. I assume red-pos, blk-neg. What is yellow? Wire run to power should be 16ga or 14ga? Thanks for your help.

Pretty sure I saw your question answered on bbc. But yellow would go to a LSS module, sonic hub or sonar hub. Tape the other wires up individually so they can�t ground out, that went to an old no longer used nmea system.
I always use 10g, but 12 would work fine. If it�s a short run 14g could work ok, bigger is usually better for long term though.



Or someone could post a pretty picture below my post for you to follow.

Click on links below for the online .pdf versions of the general manual (first link) and the installation manual (second link)
The installation manual has the wiring diagrams

onlinemanual

installation manual wiring on page 17

Download the instructional .pdf manuals to computer. Save to SD card. Place in unit when access to the manual is needed. It can be viewed on your unit and/or download to smartphone to view it. I just save the manual on the SD card alongside all the separate lakes I have.

Thanks guys, down loaded links. Will get loaded on another media. Also running 12ga dedicated power line to each separately with fuses at battery.

In the diagrham it says the yellow wire is a "accessory wake up wire". What the heck is that?

Basically, its a "switched" connection. When you power the main unit up, it energizes accessories that are connected to it.

Thanks Gamblinman, I looked again (after I posted) cct's post and saw above the schematics it said "remote start for certain Navico ..."