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The 7440 will not function in the dual bright dim mode in the 7443 socket.
The 7443 is a dual contact (d.c.) bulb. The dual contacts are connected to 2 separate circuits inside the bulb. One for bright or high beam (braking/turn signals) and one for dim or low beam (running/parking lights).
The 7440 is a single contact (s.c.) bulb. The 7443 led bulb can be used universally in either 7443 or 7440 applications.
3156 is single filament bulbs. 3156 will not function in the dual bright dim mode in the 3157 socket.
The 3157 is a dual contact (d.c.) bulb. The dual contacts are connected to 2 separate circuits inside the bulb. One for bright or high beam (braking/turn signals) and one for low beam (running/parking lights).
Compare Different Bayonet based part no. 1156, 1157, 1142, 47386, 7507