Headlamps flashing

[Rover/Scout]

Guys I have had three 72 chargers over the years and this problem is a first. After driving for more than 20 to 30 minutes the headlamps start to go on and off when i am stopped in gear or at a red light. I have check the terminal and the wires are good no burns and I replaced the dimmer switch.
Any help would be greatly appreciated.

Doyle
Longmont, Co.
713-206-2634

[Dino]

Any issues at all while driving or does this only occur when stopped?  Does it do this with low beams on only or high beams as well?
   
Try to measure the voltage going to the bulbs when you first start it up and the lights work and measure it again when it starts acting up. 
Also check your bulkhead connector, if there is a loose contact the resistance will build up and may cause some anomalies.

Let us know what you find so we can rule out some things.