Most of the guys think that the red wire on the headlight switch is the power wire for the tail lights and parking lights. Actually it only powers the blue wire which goes to the dimmer switch.
The orange wire is the power wire for the tail and dash lights and it should have full time power as long as the battery is connected. This is so the tail lights and brake lights can work without the key on and still not have to turn the headlights on.
The orange wire is powered at the fuse box by a separate red wire in the four way junction in the cab. This red wire goes into the back of the fuse panel and powers the orange wire and the hazard flasher.
Notice the orange wires in the fuse panel, lower right, They feed the stoplights the dome lights and the headlight switch, next diagram.
The orange wire going to the headlight switch is on the lower right. It must have power for the tail lights to work. Check the stop tail fuse in the fuse panel. If it is not blown then there is a wire broken. You can narrow it down if the stop lights don't work or the dome light or the flashers. \
The orange wire goes to the headlight switch and when the switch is pulled the orange wire connects with the brown wire which runs to the parking lights.
It also connects to the green wire which goes to the dimmer rheostat in the headlight switch and then to the fuse panel to the gray wire for the dash lights.
