87 LE SHOWS REAR LIGHTS WARNING EVEN THOUGH ALL LIGHTS WORK-POSSIBLE CAUSES?

 

You checked both tail and brake lights?

You might change all the bulbs and clean the socket terminals. Increased electrcial resistance caused by a failing bulb, corroded socket or bad wiring can cause the indicator light to go on.

The sensor unit itself can fail causing this problem. It's location is the trunk, drivers side behind the lining.

 

clean or change the bulbs and the socket terminals, and the sensor unit could be causing the problem in your car...

 

Do I see an echo?Thanks for the bit of info I've been having the same issue lately. I think mine is wiring, I also have my reverse lights not always engaging.