My 87 TII has no heat. The previous owner said the heater core broke. It leaked into the car.It is now bypassed at the fire wall. I figure the steam from the coolant caused the logicon to act weird.

By SEARCHING I figure I have to solder the certain points in the logicon. Also the air mix motor could be the problem. Is there a way to test the air mix motor?

I can turn the air on and the speed of the air works fine. It just won't let me select floor or face. It stuck on defrost. The small lights(tiiny square lights in logicon) work on all settings. ANY INPUT WOULD BE GREATLY APPRECIATED!!