This 1992 Chevrolet K1500 pickup came in with the complaint of no headlights. A quick check of the dimmer switch found that the switch did not click when operated. It could have easily had a complaint of no high beams or low beams but in this case, there were no headlights at all. The panel that covers the opening below the steering column had already been removed. On this truck the panel is held in place by two screws. Earlier models had four. I find it easier to remove the upper steering column bracket when doing this repair. There are four 13 mm bolts that hold the bracket to the column.
Remove the shift indicator cable from the shifter shroud or you may break it when the column drops down. Most just clip on the edge of the shroud but I have seen some that also use a screw.
Now the two 15 mm nuts can be removed and the bracket placed out of the way.
Note the position of the bracket. The edge with the turn downs is at the fire wall end of the column.
Using a small roll of electrical tape I wrap the dimmer switch rod and steering column housing together. It does not have to be wrapped tightly. Just a firm grip. It hardly ever happens but if that rod slips out of position, the steering column may have to be disassembled to put it back in place. It took over ten years of working on steering columns before it happened to me.
The upper screw can be removed with a 5/16″ or 8 mm wrench.
The lower nut is easier to remove with a wrench or short socket and ratchet.
It is a 3/8″ hex.
The switch can now be pulled off of the steering column housing. Note how the heat has discolored the wiring at the switch.
The switch also has heat damage.
The connector has a burnt terminal and melted plastic housing.
This test can be done earlier if you are unsure if the switch is the problem. It is easier to show with the components removed. Check for power on the yellow wire with the headlight switch turned on. This had power so it proved that the signal was coming from the headlight switch.
Jumping the yellow wire to the tan wire will supply voltage to the low beam headlights. Jumping power between the yellow and the two green wires will power up the high beams. There are two green wires because one goes to the high beams and the other goes to the high beam indicator bulb in the instrument cluster.
I spliced in a new harness connector.
Then installed the new dimmer switch. When installing the new switch it will need to be positioned with the rod in the socket and then the lower hole placed over the stud.. Start the screw and the nut and barely tighten them. Slide the switch up until the rod just lightly touches the bottom of the socket. Tighten the mounting screw and nut. Notice the metal retaining bar in the new switch.
It is removed after the switch is installed. Now connect the harness and check the switch operation.
I placed the turn signal switch harness connectors in the proper hold down bracket on the right side of the steering column and tidied up the wiring. Sorry no pictures of the finished job as I was ready to get out of this dirty truck.