Have you checked your brake lights bulb? If your bulbs are burnt out, the lights will not work even with power coming to the terminal. Some times, the bulb will look fine but it actually is dead. Or it could be losing contact with the socket. You should put a little thermo-electric grease on the base of the new bulb before installing it. The grease works to prevent the loss of contact as well as damage from moisture. Hope this helps.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
The brake light wire leaves the brake switch and goes into the turn signal switch. They often share the same wire: the rear turn signals and the brake lights. When turning, that side is routed through the turn flasher, but you get a steady brake light on the other side.
So you have power to the brake switch. Pull apart the connector for the turn signal switch, and see if you have power in on the brake wire (with brake depressed of course) going into the turn switch. If you have power in, plug the connector together, and see if you can backprobe the connector with test light or voltmeter, looking for power out to the rear brake lights. If power in, but no power out, the turn switch is probably bad.
It could be the turn signal switch, since the brake wire travels through the turn switch after it leaves the brake switch and then goes to the bulbs. That is how you get a steady brake light on one side, and a blinking light on the turning side. The rear turn signal lights and brake lights share the same filament in the bulbs (and the same wire). The wire on the turning side has to first travel through the flasher relay. If you have a test light, first check for power out of the brake light switch with the pedal depressed. Then check for power in and power out at the turn switch connector-power in on the brake light wire and power out on either of the wires going to the rear bulbs-if no power out, the turn switch is bad-brake pedal still depressed so you still have the signal.
I can almost 100% guaranty the turn signal switch is the problem. Power for the brake lights starts at the brake switch. power then splits from there and the third brake light gets power directly from the brake switch. Since the turn signal and the brake lights are on the same bulb power for the brake lights is routed through the turn signal switch. the switch depending on what position it is in will allow brake power or turn signal power to there respective left or right brake/turn bulbs.
If you hold your foot on the brake pedal and wiggle the turn signal and or play with the hazard switch the brake lights will almost always intermittently start to work. this will confirm a bad turn signal switch which is pretty common on GM vehicle with this style setup.
check all electrical fuses first. the brake switch that is mounted on top of brake pedal arm underdash, may be bad or out of adjustment. this switch sends power to rear stop lights when putting on the brake. if bad there will be no power going to back lights. after fixing switch check the power to stop lights. if still no power check wires and the bulbs.
RPO relay?? no power to rear lights or just brake lights?? is there power at the brake light switch? does the center high mounted brake light work? if the center light works the the switch is good. fuse #13 powers the brake lights (all)
Check the connection at the brake light switch for power comming out to the barke lights,try feeding power to the brake lights manualy using a jumper wire from your fuse box or battery,unplug the wire from the switch and put power to the harness if everything is OK the brake lights will work,then you need a new switch.
Bad or borken wire harness in the steering coloum. check power to brake switch, should have power on one side, if not check the fuse if fuse is good and you have no power then your turn signal switch or harness is bad.
CK THE BRAKE LIGHT SWITCH ON THE BRAKE PEDAL FOR POWER IN & OUT WHEN ON THE BRAKE.IF IT IS OK U MANY HAVE A PROBLEM WITH THE TURN SIGNAL SWITCH.POWER GOES THROUGH THE SWITHC TO THE REAR LIGHTS.WIGGLE THE TURN SIGNAL SWITCH WHILE STEPING ON THE BRAKE IF THEY LIGHT OP THE T/S SWITCH IS BAD.
check behind the brake peadle for a little button that pushes in and out when the peadle is pressed(this is your brake light switch) some cars have more than one of theese. manualy let the button out if the light works the switch is good if it does not disconect the harness from the switch and take a small piece of wire and jump the two prongs on the harness if the brake lights come on then you need a brake light switch. if this doesnt work check for power at the switch. if no power you have a bad fuse if there is power and you already jumped the wires to the switch then you have a broken wire between the switch and the tail lights.