I have a 2004 Honda Accord Coupe Ex 4clyn. When I use the brakes, my brake lights do not light up, except for the high mounted center brake light in the rear window. But when I press the hazard lights button, they work fine then. What could be the problem?
Brake lights and hazard lights are separate circuits. (Separate switches)
Check the bulbs for a burned out filament. These are double filament bulbs. Also check the sockets for good grounding.
Slim chance this is the fault though with both sides out.
All my fuses are good and the bulbs are good. They work fine when I turn on my hazards.
The brake circuit runs through the flasher unit so I would check out.
Some cars use separate switches and circuits for the tail lights and the third brake light. I’d check the brake switch on the brake pedal under the dash.
do you have a cruise?
next time you are out driving, engage the cruise, let it settle out, then tap the brakes. see if the cruise shuts off. if the cruise shuts off then the brake switch is good. if it does not shut off then the brake light switch is broken.
Since the OP stated the third brake light turns on it appears that the brake switch is working. It is the path to the side rear lights that has the problem so that points to the flasher unit.
Could it still be the flasher unit even though the hazards work fine?
I think they are two seperate units so yes I still think the problem could be with the turn signal flasher unit.
Not on a Honda
Your car has a safety indicator system. This is that symbol on the dash that shows a door open. It also shows you that a brake light bulb is not working. If either the right or left brake light bulb has a burned out filament, a line under the symbol should light up. The high mounted brake light is not in this circuit.
If you are not getting the light bar below the symbol and nether left or right bulb is working , then the relay in the safety circuit has burned out. The relay is called a failure sensor and is located in the left taillight housing.
The emergency flashers and the turn signals are separate circuits from the brake lights. The don’t even share the same bulbs or color of lens. The turn signals are amber, not red.