93 tercel DX auto. Turn key to "on", and dash lights illuminate but as soon as I use some other electrical function such as step on brake they go out. When key is turned to "start" there is a sound like a short coming from under the dash from a module to the left of the blower motor (as you face forward in the passenger seat). Also, the gear shift lever will not move from the "park" position without using the gear shift unlock gizmo under the tab near the lever.
What is that module? I can't seem to find a reference to it anywhere.

Problem solved. Although brand new electronic battery tester showed 97% charged and 12.6 volts, under load battery went to zero. Old battery replaced and car starts and runs great again.