No turn signals or brake lights on left and right but brake light on top

As in the previous comments the brake switch wire goes to the turn signal switch and the third brake light. Since the 3rd brake light is working, the problem is in the turn signal switch. When the switch is centered, both brake lights have 12v to them. When you make a left or right turn, the switch has to switch connections between the turn signal blinker and the brake light circuit for the appropriate illumination of the proper light sequence. Buy a new turn signal switch and temporary plug it in. You will see the proper operation.

Get a wiring diagram from the Free portion of the Autozone site. It is a little work to separate the Help categories at the bottom of their Webpage.

I have heard of SOME 4-way flashers that are built into the turn stalks causing problems. The contact pins for the turn signals are shared as 4-way flasher pins. Try clicking the 4-way flashers off/on about 20 times and then use the left turn signal. It has been known to reseat the contact pins.

The wiring diagram I mentioned would show where the tailgate top light gets its power. One feed should go to the brake light switch for the brakes and another feed should be the flasher feed.

As I see it, you have 2 extra lights going on when you use the left turn signal. Those 2 lights are the tailgate light and right turn signal. The wiring diagram should show the places where the wires are close enough to cross. I am thinking the 4-way flasher is the only place where the top tailgate light gets flasher power; the rest of the time the tailgate light is a Brake light.

I do not want to spend your money on an unnecessary turnstalk and that is why I say to look at a wiring diagram and see if there is anyplace where the wires could cross.

Last, trailer hitch plug. All wires are bundled with left turn, right turn, and brake light in the trailer hitch plug. Corrosion could connect the terminals.

Would like to know what you found.

need to check the multi-function switch. the brake light signal goes through the turn signal switch on the steering column. the brake lights come on if the turn signal is not being operated. the circuit for the brake light can loose contact in the switch.

my oldsmobile 1995 cutlass supreme has the same problem, so I replaced turn signal switch.

I think your trouble is in the turn signall switch, just had the same trouble on my truck. Turn signall switch is about $250 because it is actually turn signalls, wipers, washers, 4 ways, and dimmer all in one.

Hello. The symptoms you are describing are likely due to a poor ground. Temporarily install a new ground wire by securing a piece of copper wire to the frame with a self tapping screw. Use this ground wire along with the hot wire to see if each of these lights works. If it does, trace the ground wire back to the frame, unscrew it and clean up the metal with emery cloth so you reestablish a good ground.

Check for power at the turn signal switch. White wire comes from brake switch switch into the turn signal switch. The brake light switch is working because the high mount brake light is working..right? Do the turn signals work ok? if so, then the wiring is OK. The brake signal wires that come out of the turn signal switch are dark green(right) and yellow (left).

It is most likely your brake light switch. The wiring from the brake light switch goes to the turn signal switch. When the turn signal switch is centered both brake lights are connected, unless the switch is faulty. When the switch is to the left only the right light is connected to the brake light switch and vice versa. A bad switch can cause all kinds of problems with the brake lights as well as the turn signals.
To replace, locate the brake light switch at the top of the brake pedal (on the mounting bracket). Unplug the connector. Loosen the locking nut and remove the switch. Install the switch and adjust the height so the switch activates at the right position. Reconnect the connector and check for proper function.

third light is different circuit. saftey reason check fuses grounds wires

No, but that's probably where your problem is. The wires get the hell beat out of them by stones, and then they short out and cause problems. I would take a look at it.