high beam works. low beam dont work

[yellowtr3]

hi.
son just bought an 1982 720 truck.
first thing we find is the high beams work but not the low beams.
its a 4 light set up
using my test light i have determined that when the high beams are on, the low beams are also.
but when we use the column switch to go to low beam..no lights.
determined that all sealed beam units are working properly. 1 was not has has been replaced by new.
cannot for the life of me follow the wiring diagram. and i have been following wire diagrams for 40 years. what engineer dreamed up this mess of alternate routes?

ill have more questions as we get into the restoration of this truck.
thanks
Frank

[yellowtr3]

Still struggling with the wire diagram.

It appears that power comes directly from the battery via a fusible link to the light switch on the steering column.

It then appears that we go from the switch directly to the low beam without passing through a relay. No?

Then for the high beam it would appear that we do pass through a relay to take more amps to the high beams. No?

So where do the lights go to ground? Is it the red wire? The red wire runs everywhere it seems but I never see it go to ground. At least not yet.

[yellowtr3]

Still struggling with the wire diagram.

It appears that power comes directly from the battery via a fusible link to the light switch on the steering column.

It then appears that we go from the switch directly to the low beam without passing through a relay. No?

Then for the high beam it would appear that we do pass through a relay to take more amps to the high beams. No?

So where do the lights go to ground? Is it the red wire? The red wire runs everywhere it seems but I never see it go to ground. At least not yet.