My wife has about 10,000 miles on her 2003 CRV EX. Recently the dome
light sometimes doesn't work.

The light is supposed to go on when you open the door but doesn't
sometimes, especially at night. Then, during the day it comes on when we
open the door. I tried the dome light switch --on the light itself-- in
all three locations with no effect when it doesn't work.

Today she brought the CRV for an oil change and the service department
"checked all door switches" and said the light worked for them. My wife
confirms it worked then. (Of course!) Tonight the light again doesn't
work. I can open any door, put the light switch in any place and the
light won't work.

It seems to me that this is not a door switch. It must be some part of
the circuit common to all the doors. Any ideas? How do I get service to
fix it?