a real easy way to do the speakers is to run an aftermarket 4 channel amp cut the wires off of the stock speakers. run your own wires from the speakers directly to the amp. run the power and ground for the amp. then find the remote wire, usually blue on a pioneer. adjust the levels on the amp and the head unit and you can get good sound out of.. Our complete Ford radio wiring diagrams make it easy to find the stereo wiring harness colors, speaker wire colors, and speaker sizes for your vehicle. Each Ford radio wiring diagram is based on real-world installs or verified info from our helpful community.
So I have a source for most of the diagrams published by Ford for the 1994 Explorer. These pictures are huge so sorry for that. but that's good also so we can read them. Picture descriptions are above the pics. Due to the source I can't guarntee that all of the diagrams are for a 1994 Ford.. 1994 Ford Explorer Stereo Wiring Information Radio Battery Constant 12v+ Wire: Light Green/Yellow Radio Accessory Switched 12v+ Wire: Yellow/Black Radio Ground Wire: Red or Black Radio Illumination Wire: Orange/Black Stereo Dimmer Wire: Light Blue/Red Stereo Amp Trigger Wire: Blue Left Front Speaker Positive Wire (+): Orange/Light Green