That really blows Greg (sorry, couldn’t resist buddy). Unfortunate it was a costly repair, but glad you were able to get the problem resolved. Glad you shared your experience so others could be aware of the potential issues caused by back feeding an ECU, most wouldn’t so kudos to you. Modern vehicle are very sophisticated and complicated, containing multiple computers, modules, Multiplex / Can-Bus wiring, one misstep can prove costly.

I too have received several PM’s asking about illumination interfaces, in my case (2012 SR5) green wire is positive (+) when parking lights/headlights are turned on, gray wire is illumination ground (-). Gray wire controls light dimming function. These wires can be found at any switch that illuminates when you turn on your lights, again in my case, there was an unused harness (with white plug) behind dash panel that I tapped into. Always test wires with a multimeter before interfaced to insure they a correct as different year Runner’s or different trim levels may differ in color.

Both Slee and AOB switches are low amperage switches (3 amp max), meaning you must install a relay to control whatever component you want to turn on/off. Switch is basically a trigger, load is handled through relay (generally rated around 30/40 amps). Illumination portion of switch are LED, which means they only draw milliamps when energized, so they will not overrate the factory system. Keep in mind if you’re adding lots of switches and additional dash lighting, measure draw prior to installation as you may need to add a relay, factory wire is trigger, relay handles load.

To those of you who have limited 12 volt experience might I offer a few suggestions? Have a plan on what you want to add to your vehicle especially when it comes to wiring, fewer connections are better’er. Review all wiring diagrams and/or schematics, if you don’t understand or are confused on what needs to be done, stop, seek help or pay to have it done. Plan how you will run your wires, if routing through the firewall, try to use factory grommets whenever possible, once wire(s) pass through grommet seal with silicone. Don’t push grommet to the side then run wire between edge of grommet and metal firewall, causing wire insulation to rub on metal edge cutting insulation causing a short circuit. If none are available, drill a hole in firewall and add a grommet, rubber or plastic are acceptable. All external wire connections should be waterproof! When installing ground wires, ensure metal to metal contact, remove any paint that may between connector and metal surface, use a nut and bolt whenever possible, then coat with a sealant like undercoating. Most electrical issues are caused by loose or corroded connections. Encase all wires in wire loom to protect them from possible chaffing or cutting on sharp metal edges. Route all wires away from moving components or heat sources. Fuse all power wires to prevent an electrical fire! When cutting wires to length, cut longer then you need, I like to use the analogy “measure twice, cut once”, better too long then too short.

Verify switch wires and factory wires are correct before interfacing. When making wire connections, I prefer to use solder and heat shrink or high quality electrical tape (3M Super 88), butt connectors can also be used, but require cutting of factory wires. T-Tap’s are the worst type of connection, yes they are quick and easy to use, but they cut the wire when crimping and over time will cause intermittent connection issues. Route wires to connection point, make connection, protect connections, and then test for correct operation. Once verified, protect harness with wire loom, nothing worse than opening up a dash only to find wires running everywhere “wire spaghetti”. If done correctly, the only failure should be because the item you added failed, not you’re wiring. Reassemble and enjoy years of operation.

Here are schematics for both switches...................
Slee
Slee Wiring Diagram.pdf
AOB
AOB-SW800 Wiring Diagram.pdf