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1969 Mark III High Beam Issues

I have removed the 4 amp fuse that is to kill the high beams with no result. I have pulled the relay that is bolted to the base of the steering column and checked it on the bench – OK. I reassembled everything and the high beams functioned properly. After a few days, high beams stuck on again. Dash indicator light is on when high beams are on. Floor dimmer switch seems OK, but both high and low beam wires are hot all the time when this problem occurs. I am tempted to change the relay on the steering column, but thought maybe you could help me first. Thanks in advance for considering this.
Forgot to tell you my car has the auto dim feature, though I guess the 4 amp fuse I mentioned is only on the auto dim cars.
Greetings –
From your description I would start with the 4 amp fuse removed and the relay unplugged and then proceed to diagnose the circuit as a Non auto dim system. Your dimmer switch or relay could be faulty and intermittent. The manual system dimmer switch differs from the auto dim switch. One of the electrical plugs at the relay will plug into a Manual type dimmer switch for test purposes. If you do not have a manual system dimmer switch available for testing, the wires at this plug can be jumped to test the circuit. A wiring diagram for both the auto dim and manual dim is necessary to understand how the system works and the correct wires to jump. Do you have these wiring diagrams.

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