Porsche tail lights not working. Disconnect the battery. Before any intervention on the electrical system of your vehicle, you must always disconnect the battery. This will protect you from electrical shock or damage to anything during operation. Loosen the nut that secures the ground cable to the negative battery terminal with a socket or socket wrench. Disconnect the cable and place it on the side of the battery. You can find the negative terminal by looking for the letters “NEG” on the battery or by looking for the “minus” (-) symbol. You will not need to disconnect the positive terminal.
Wear eye protection. You’ll need to inspect the underside of the board for this project, so it’s important to wear safety glasses to make sure you don’t get debris in your eyes. You won’t need gloves for this project, but you can wear them so you don’t get pinched by wires. Eye protection in the form of a mask provides the highest level of protection. For this task, eye protection in the form of goggles is sufficient.
Porsche Taillights Not Working – Locate Brake Pedal Switch
The brake pedal switch is a button located along the axis of the brake pedal above the footrest. When you step on the pedal, the axle presses a button that turns on the brake lights.
If you don’t know where to find the brake pedal switch, consult your vehicle’s service manual. The switch will have a flexible cable coming out of and mounted directly behind the brake pedal.
Disconnect switch harness
The wiring harness for the switch will be held in place by a plastic cover. Press the latch on the plastic housing to release the flex cable from the switch, then pull the plastic part of the flex cable to release it. Do not pull on the wires as this can cause them to become disconnected or pull out of the wiring harness. Be very careful not to break the plastic clip.
Porsche Taillights Not Working – Visually Inspect Wiring
Look inside the braid for signs of burning or melting. If the wiring has overheated, the flex cable may have been damaged and the brake light may stay on. Any sign of damage within the wiring harness can cause problems with your brake lights. A damaged pigtail must be replaced for the brake lights to work properly. You may need to order a brake light switch flex cable from the dealer for some vehicles if they are not available at your local auto parts store.
Porsche Taillights Not Working – Test Switch Return
The switch itself is a long button that is pressed when you press down on the brake pedal with your foot. Under the dash, press down on the pedal or the button itself and see if the button pops up when you release it. If not, it probably means the button stays in the “on” position. If the button is stuck in the “on” position, the brake light will stay on. Have a friend stand behind the car to see if pressing the switch will affect the brake lights. If the button does not affect the light, the fuse may have blown or the switch itself may have failed.
Bad taillight bulbs
If the fuses under the hood and in the cabin are good, the taillight bulbs are the next culprit. This usually involves removing the tail light cover, although some cars have an access panel where you can reach and unscrew the bulb from the lens. The best way to identify a faulty light bulb is to remove it from its socket and inspect the filament carefully. The filament is the wire inside the light bulb that creates the light. A broken filament means there is no light and you will need to replace it with a new light bulb. Have you ever changed a light bulb for a new one and it still didn’t work? Keep reading.
faulty lamp holder
Sometimes the outlet that the light bulb is plugged into can fail. This is usually caused by corrosion causing moisture to enter the socket. However, it can also fail due to poor cable connections at the back.
If both the bulb and the fuse are OK, check the condition of the socket when removing the bulb. Look for any discoloration such as white, blue, or brown, as well as bent or broken contacts. At this stage, it is also recommended to check the electric current with a multi meter at the output. If power does not reach the pins, it means there is a problem somewhere in the power line.
Porsche Taillights Not Working – worn wiring
If there is no power in the outlet and the fuses are good, most likely a wire is damaged or broken somewhere in the line. At this point, you will need to get the wiring diagram and visually inspect the wires along the tail light circuit for broken wires or cracked insulation.
Also be sure to check the body weight coming out of this circuit. A dirty, loose, or broken ground wire can also cause power to fail at outlets.