That looks about right. Less than 10 amps total current draw on high beam should not cause the circuit breaker to cycle. Try this- - - -disconnect the wiring harness at the dimmer switch, and jumper the wires together so the high beam lights are on, then take a test drive. Is there a plug at the dimmer, or do the wires connect individually with ring terminals and screws? Either way, the idea is to bypass the dimmer to see if there's an internal current leak that's overloading the circuit breaker. If the lights don't flash or flicker with the dimmer switch bypassed, replace it. If they continue to flicker, replace the light switch. Getting an unwanted current leak to ground in a dimmer is a pretty common problem due to corrosion inside the switch. As I believe I said before, dimmer switches live in a pretty nasty environment.
Jerry
