What is a key 2 wire?
The Key 1, Key 2, and Key GND wires will be used to interface steering wheel controls if your vehicle came equipped. Most newer vehicles will also need the Axxess ASWC-1 to translate the steering wheel controls to this stereo.
What color wire is the steering wheel control?
SWC Interface Wiring
There are two wires used for steering wheel controls. Each interface (either stand-alone or as part of a multi-function product) has one blue/yellow wire and one black wire with a stereo-type 3.5mm plug. Both wires accomplish the same purpose: transfering the SWC signals to the radio.