If any of you are familiar with the Garmin Nuvo 39X and 59X series you know that it comes with an over engineered, cumberson, and semi-useless wire and power harness (see above picture) for the cradle that:
- Requires you to hardwire it directly to your electrical system for 12V power. Either directly to the battery or spliced into a 12V source somewhere on the bike. This perpetually locks the cable/cradle to a single bike, whether you want to use a GPS or not on any given day. The cradle and wire are there forever, until you tear them off.
- Has hardwired line in/out jacks in the year 2018 where everything runs off Bluetooth. Seriously Garmin?
- Has a USB port that is power only, and supposedly only works on iPhones (so in actuality it’s not a universal USB port per the USB standard).
Anyway, here’s a mod to convert this mass of mostly useless copper into something useful and specific for the H2 SX, or any other bike that as a 12V outlet for that matter. Note this writeup is specifically for the Garmin 595lm wiring harness.
Since I have no use for hardwired audio (as stated, everything is Bluetooth these days) and the H2 SX has a 12V socket built into the dash (SE only), I modified the harness down to a streamlined version which can easily be taken on and off the bike as needed. This means if you own multiple bikes you can use one wire harness on all of them instead of buying a hardwired power harness for every bike.
Take the power cradle apart, taking note how the locking button at the top comes apart . . . don’t lose the small spring.
Basically I dead headed the internal large connector for all hardwired audio and USB function, just cut it off. Leave the second smaller connector with the red and black wires, this is the 12V power source.
Cut the overall harness to a needed length, taking into account your GPS mounting location on your bike relative to your 12V socket, leaving extra slack for turning the handlebars. This will remove all the extra connectors. Then strip back the end of the wire bundle and locate red & black. To verify you have the correct wires, just check continuity between the small internal connector and the wires at the end of the bundle. Cut back all the other now extra and useless wires within the bundle.
Next, solder red (12V) and black (ground) to the appropriate locations on a cheap, fused (important! 2-3A recommended) 12V cigarette adapter (you’ll have to disassemble to do so). Red (power goes to the center post, and black (ground) goes to one of the tabs on the side of the adapter. Here’s the end result:
Next, re-assemble the cradle shell, making sure the water seal gasket is undisturbed. Check the cradle lock button to ensure you re-assembled it correctly. Here’s the final cradle. Slim . . . functional.
The reason for keeping the original cable harness, despite all the extra wire within, instead of just replacing it with a very thin two wire setup is the harness that comes with the cradle is waterproof, and has waterproofing and strain relief built in where it enters the cradle.
Once that’s done just add the Ram mounting hardware to the back of the cradle per instructions, slap onto the bike, plug it in, and you’re ready to roll. The added bonus is that the 12V socket is linked to your ignition, so you can’t accidentally leave the GPS powered on for days on end, like a hardwired setup, as it will drain your battery:
Garmin does some inexplicable things with their hardware. I know why they do it . . . to sucker you into buying multiple harnesses for all your bikes. Not gonna happen Garmin. They should really offer various harness options that can be disconnected at the cradle side and not force you to lock the cradle and enormous wire harness to your bike/battery.
Nothing a little re-engineering can’t fix.