* Power Source: The system gets its power from the vehicle's battery.
* Multi-Function Switch (Turn Signal Lever): This is the stalk on your steering column. It contains switches that activate the turn signals (left or right), as well as the hazard lights. These switches complete a circuit, allowing current to flow.
* Brake Pedal Switch: This switch is located near the brake pedal and closes a circuit when you press the brake pedal. This sends power to the brake lights.
* Turn Signal Flasher: A flasher unit, usually a small electronic component, interrupts the flow of electricity to the turn signal bulbs, causing them to blink.
* Wiring Harness: A complex network of wires connects all the components. The wires carry electricity from the power source, through the switches, to the bulbs.
* Bulbs: The bulbs (incandescent or LED) are the light-emitting components. They light up when the electrical circuit is completed. Separate bulbs are typically used for turn signals and brake lights, often in the same housing. Some designs might use a dual-filament bulb, where one filament is for the turn signal and the other for the brake light.
* Ground: A complete circuit also requires a ground. This allows the electricity to flow back to the battery, completing the loop.
How they work together:
1. Turn Signals: When you activate the turn signal lever, it completes the circuit to the corresponding side's turn signal bulbs via the flasher unit, causing them to blink.
2. Brake Lights: When you press the brake pedal, the brake pedal switch closes the circuit to the brake light bulbs, causing them to illuminate.
3. Combined Function (brake and turn): When the brake pedal is pressed *while* the turn signal is activated, both the brake lights and the appropriate turn signal lights will illuminate. This is because both circuits are completed simultaneously.
If either your turn signals or brake lights are malfunctioning, the problem could lie in any of these components: blown bulbs, faulty switch, wiring issues, a bad flasher unit, or a problem with the ground connection. Troubleshooting would involve checking these components systematically.
