Have you checked the fuses? Have you run a circuit test at the brake light socket? On the circuit test I mean take the bulb out, put a circuit tester on the two leads and have someone press on the brake with the key on. Have you checked the bulbs? These are all normal first line checks you should try first. Also, have you checked for current at the brake switch? Has it got power going to the switch? Do you have power out when you press on the pedal? It might be that the switch isn't adjusted correctly and when you press on the brake it's not making contact because of the travel.
Yea, you need to get a multimeter. What your looking for is the point at witch you are losing current. The path of the current should start off at the ignition switch as soon as you turn the ignition switch over. It should send current to your brakelight switch (which is located on the engine side of your steering column, just below the dashboard and/or your indications lights) now, from the brakelight switch, as soon as you press on the brake pedal. It presses the to connectors together and passes the electrical circuit on to the white or yellow wire... most for that year are yellow... but it being a weird year for changes with automotives. Some, like mine actually pass on to the white wire. With that being said, the white or yellow wire out of the brakelight switch should have power after pressing n hold down on the brakes. That wire then splits apart and goes to several different areas but the only wire that is a concern is the one that goes into the brakelight fuse. As long as you have a good and properly ampered fuse installed. The current should flow through the engine compartment wiring harness and tap into a relay. (Which should be located on the fire wall, center right it's a four prong relay) Once that power is received to the relay. It sets off the relay and let's power flow back to the taillights. From the tailights it goes through the bulb and then follows the ground wire back to the ground wire which in turn returns it to the negative side of the battery. To complete the circuit. Get a multimeter. $10 to $30 bucks for a simple one. Put the multimeter on DC volts and hook the red lead to the power side and ground the black lead to any decent ground. Start from the beginning and follow that circuit. The the ppoint in which you lose power?
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