by Joachim Gruber » Mon Nov 20, 2017 6:38 pm
Rich,
I assume that the nav-light switch has an internal resistor which automatically dims the gear lights, when turned on. If that's so, then the resistor may be fried or otherwise disconnected/broken. This should be easily testable with a multimeter. Since the FAA considers resistors "standard parts" your A&P should (I believe) be allowed to repair the switch by replacing or resoldering the defective resistor/connection.
Joachim
1967 260B