Somehow original post disappeared. First, swap the bulbs side to side and see if dim bulb moves. If so, bad bulb. Buy new from marine beam.com.
If new bulb is dim then suspect extra resistance in the wiring. Clean all connections on that branch. Dennis C. Sent from my iPhone _______________________________________________ This list is supported by the generous donations of our members. If you wish to make a contribution to offset our costs, please go to: https://www.paypal.me/stumurray All Contributions are greatly appreciated!