Only three major components in the brake light system: Fuse, Switch, bulb.
Fuse is in the main interior panel just above the hood release.
Switch is part of the pedal assembly under the dash.
At the bare minimum you will need a twelve volt test light or meter to check for voltage at each of these components. You should have power through the fuse to one side of the switch at all times. When the brake is depressed, the switch closes and 12V should appear on the other side of the switch as well. If both those checks are good, move to the build and look for twelve volts at the bulb when the pedal is depressed. If twelve volts appears on both sides of the bulb you have a broken ground wire. If no twelve volts is present you have a break in the harness from the switch to the bulb.
never done a tercel before, but generally the back lights and brake lights are reached by going into the trunk or hatcback. you may have to pull back some lining to reach the lights
If it is the tail lights, it is the headlight switch. If it is the brake lights, it is probably the brake light switch. I really don't know how to replace the bulb in the 3rd light. change the brake light bulb first it may be shorted causeing the other problem
Try checking the bulb, the brake light bulb may be blown.
If it says 'Brake Light Failure' or similar, your brake light is out. change the bulb.
There are three black caps that screw off in the trunk behind the brake light itself unscrew them and the assembly comes out then change bulb
Why not just remove the bad bulb and look see what model it is?
carefully
Your brake light is probably brake fluid low or emergency brake on. Rear brake lights are replaced by removing the lens and replacing the dual filament bulb.
1995 Toyota Avalon brake light bulb lamp replacement procedure: Purchase the correct replacement brake light bulb(s) first, before disassembling the vehicle. See sources and related links below for replacement brake light bulb information. Then consult your owner's manual for the replacement procedure. As simple as it sounds, the owner's manual is the best place to start for brake light bulb lamp replacement instructions and illustrations. You may want to consider replacing both left and right at the same time in order to keep brightness and color equal (optional).
Bulb is probably defective. Replace it.
it means a brake-lamp bulb has burned out
it's a 921 it looks like an oversized 158 bulb