[68RT]

Switch is not locking in the high beam position. You should feel the snap over from high to low and back. Right now the lever is just reaching the high beam postion for flashing the high beams. Must travel slightly more to change over if switch is not stuck.

 

[PCRMike]

Have seen them melt down, and have also more often seen them out of adjustment. It is on the steering column (I think still in 91) and when you pull the stalk toward you, you will see a metal rod push into a plunger switch. There should be two screws/bolts that allow it to slide. Adjust as needed for it to click when you pull it.