Nissan Repair: Nissan daytime lighting problem, daytime lighting, lighting problem

Question
1990 Nissan pickup right daytime headlamp lights intermittently (mostly not). All lights work correctly when lighting switch is set to on positions. Left daytime light operates (after engine starts, not when ignition key is fully on before starter is engaged). Sealed beams are new. Where do I look? What do I check?
Thanks

Answer
Ted,

There is a relay that is grounded after the truck is started for the daytime lights.  I would replace both relays as you say one works and one does not.  I would replace both since the other relay is soon to follow.  The relays should be under the hood in the relay box.  Switch the relays left to right to verify my postulate.