On the '88 2.6E, I have the 'light is out' warning light glowing most of the time but have checked and double checked all lights and they are all functioning!! It is frustrating. Any ideas?

Third brake light - OK
License plate lights - OK
Headlights, taillights, turn signals, marker lights, fogs, backup, parking lights, can't think of others at this moment! Thanks for input

Via LG G3 mobile device

__________________
Dale