Probably bulbs. There are 2 filiments that are in the tail/brake lights. One for the tail and a second brighter one for the brake. Try replacing the bulb on one side first and check it. ==Additional Information== It is highly unlikely that the brake light filiments in BOTH bulbs would fail [burn out] at the SAME time. Although there are several possible causes including wiring, connectors, brake light circuit fuse, and others, BUT since BOTH lights are not working, I suspect that the MOST PROBABLE cause is a MISADJUSTED brake light SWITCH. I would first replace the brake light circuit fuse with a KNOWN good fuse. If that does not correct the problem, the brake light switch should be your next component checked. Next, I would properly readjust the brake light switch. The switch is adjusted by means of a threaded neck on one end of the switch, from which the actuating "plunger" protrudes. That threaded neck screws into and out of a threaded hole in a bracket which usually is mounted on a bracket to, or the metal frame for the dash board/instrument panel. When the plunger is fully pushed into the switch, the contacts are pushed "open," preventing flow of electrical current to the brake light wire[s] to the bulb filiments. When the plunger is released and allowed to fully extend, the switch contacts close, allowing current to flow to the filiments. When the switch is PROPERLY ADJUSTED, and the pedal is fully retracted ["back"] the brake pedal arm holds the plunger fully in, and therefore, the switch "off." When the brake pedal is depressed, it moves away from the switch allowing the plunger to extend and the switch to close, turning the brake lights on. Both lights are fed through the same switch and wire harness to the split to the two bulbs, and again, BOTH being out simultaneously suggests the switch, or it's adjustment, may be At Fault.
to warn the drivers behind your automobile that you are slowing down
If the back dash light will light when the brakes are applied but the two tail lights will not light up, there is probably a short in the wiring somewhere. It could also be that the fuse for the brake lights is burned out.
In the back should be tail lights which always come on when the headlights or parking lights are on, and stoplights which come on whenever the brakes are pressed. The stoplights should be brighter than the tail lights, but they should be separate.
Fog lights are in the front; they are commonly referred to as "brights" because they are the brighter of the two standard headlights. Brake lights are in the rear; they light up when pressure is applied to the brakes or when the car is in park or reverse.
Bad ground, usually at the rear lights.
Most probable a broken bulb somewhere.
If you just barely touch the brake pedal the brake lights will come on but the brakes will for all intent and purpose not be applied.
Where is the fuses for the brakes lights Buick Rivera 1970
you have a short in light switch replace light switch
There probably is only one cause for your interior lights to go on when you apply the brakes. There probably are brake light wires and interior wires that have warned together.
Many bulbs are dual element, check it out, it may be why the brake part lights up but the other doesn't.
check the contacts on the brake light bulbs correspond with the terminals in the holder, eg not a single contact bulb in a double contact holder
TRy changing your brakes and closing your doors while driving.
Sounds as if the wires at the rear of the vehicle are mixed up. Check to see if the brake lights come on when put into reverse gear. That will rather confirm the hosed wiring.
They certainly should do. If not, the vehicle should not be driven until they function correctly.
Check the switch at the brake pedal .
Check stop light switch - usually located at the upper end of the brake pedal under dash
check the multi function switch. I hava a 96 Chevy Monte Carlo and I had the same problem . I changed the multi function switch and the brakes lights now work. the rear brake lights run thru the switch on the turn signal circuit. try it and see.
When you press the brakes, the lights brighten up mainly to alert drivers behind you that you are slowing down or stopping. It prevents accidents
You do not have the trailer lights connected properly.
with the park lights on both left and right side are lite. but when the brake is applied the right brake lights up and the left goes out(doesn't light up)
It depends on the quality of the brake pads that were installed. It could also be a "glazing" of the pads and rotors due to your personal braking tendencies. I.E. riding the brakes or braking very slowly and early at red lights.
check fluid level
get the whole care re wired also dont turn on your hazard lights!!!