Strange High Beam problem

[cospinner]

Ok, while out tonight for a shake down drive, the high beams on my 70 280SL suddenly came on by themselves.  I tapped the floor switch a couple of times before they went out.  Then 30 seconds later they came on again, but this time when tapping the floor switch, the dash light and the brights will not turn off.  The low beams turn on and off, but the high beams stay on.  Turning the light switch on and off does not help.  Did something come loose on the floor switch or should I look at the fuses? 
Thanks.

[Benz Dr.]

I think you have serious problem and I would disconnect your negative battery cable for now if I were you. It could be in the light switch or the dimmer switch, or somewhere else, but whenever you have something that won't shut off, it's not good.

[Tyler S]

Most likely there is an issue inside the flash to pass portion inside the indicator stalk. This circuit is always powered regardless of headlight switch or dip switch position.