I have a 2001 Mazda MPV that left brake lights does work but, the tail lights work (which is the same light). I replaced the light bulb. Nothing changed. Please help!!!
If the brake lights and the tail lights both work, why do you think that there is a problem?
I think the word “not” is missing from your original post.
Does the left brake light work, or not? You said, “. . . left brake light does work but, the tail lights work.”
Huh?
If it doesn’t work, check the fuses, the wiring connections at the bulb receptacle, and, finally, the wiring itself.
The left brake light and the high center brake light are both supplied with power after they pass through what Mazda calls a joint connector located behind the left kick panel. This is just a splitter connection. You might want to remove the left kick panel to see if there’s a problem with the connection from this joint connector to the left brake light.
Tester
Sorry, let me clarify my mistake. When you press on the brake pedal the brake light doesn’t light up. If I turn on my lights the same light will work. How can this be?
Follow what Tester has said. The brake light and tail light are on separate circuits, and the left brake light is not getting 12V signal when it should. The other lights, center and right, are. Chances are there is a break in the circuit to the left brake light. The joint connector mentioned by Tester is a logical place to start. If the signal is present there, the break in the circuit is between that connector and the light housing.
It can be because it’s a dual filiment bulb. One bulb, two circuits. Did you replace both bulbs with new ones or used ones that you thought were good?