The thin red wire is your battery make sure you solder the inline fuse to that the other end to your battery source in my case I didn't want to drill holes in my dash so I mounted the SMD TM1 in my trunk the thin yellow wire is for your remote turn on I hooked mine to one of the amps I'm running the last black thin wire is your ground trust me I've tested this a few times now your left with the thick black and white wires the white is for your power to your fan the thick black wire is for your ground to your fan this is the proper way to set the device up if your using a capacitor /power cap attach the thin red wire to the positive being you attached the inline fuse that came with the kit