Thanks Rico and Gremlin!
I looked at the left front turn signal bulbs as you suggested- that was the
corner that was hit and the previous owner reported that the problem started
after the accident.
When I removed one of the two yellow bulbs, I cleaned up the socket a bit
and found one of the two little round tabs that are usually on the bottom of
the bulb laying across the contacts at the bottom of the socket. Apparently,
the previous bulb in that socket was broken in the accident and that little
round tab had broken off. I removed it and now everything is fine. (Except
for the hours I spent trying to find the problem! At least now I have
experience in taking apart a steering column and dashboard!)
Bluff City, TN USA