Hi there,

If your daughter's 91 is a sedan, also consider a fault at the harness connection to the left tail light assembly. The L-shaped plug there has two black wires in it, which daisy chain the reverse lighting from the left to the right tail light assembly. A bad spot on the plug there will often cripple both backup lights.

If your daughter's 91 is an automatic, you may be able to fix the lights the same way I did in my daughter's 83, my 84, and then once more in her 91: Fix Your Backup Lights

It isn't so easy if she drives a stick.
--
Art Benstein near Baltimore

Middle age is when you choose your cereal for the fiber, not the joy.