[OG68]

Headlights don't use a fuse There is a circuit breaker internal to the switch.
I would start at the dimmer switch. The blue wire is common feed from the headlight switch. It should have 12 volts whenever the headlights are on. Green is high beams, tan is low. If the high beam indicator is on that means the green wire should have 12 volts too.
Does pressing the beam selector switch turn the indicator on and off?

Another possibility is that the high beam indicator bulb socket (green wire) has been replaced with a regular dash light socket. ( grey wire).

But first check voltage on the blue wire at the high beam switch to a good body ground. That will tell you which direction to go next.