How does the brake light circuit work in a car?
A typical brake light circuit The most common brake light switch is the simple mechanical type mounted close to the brake pedal arm. When the pedal is depressed, the switch automatically closes to turn on the brake lights. The other type of switch works hydraulically and is operated by the pressure of fluid in the pipes when the brake is applied.
What happens when the brake light switch is not working?
Brake light switch is installed above the brake pedal. Many vehicle systems including Push-Button start, Antilock Brakes and Vehicle Stability Control cannot operate if a brake light switch is not working properly. The brake light switch serves two major functions. First, it turns on the brake lights when a driver presses the brake pedal.
How do you test the brake light switch?
In some cars, the testing procedure involves testing the voltage at the brake light switch connector when the brake pedal is depressed and released. In other cars, the service manual recommends testing the switch continuity with the pedal depressed and released. If there is no voltage at the brake switch,…
Where is the plunger on a brake light switch?
The brake light switch has a plunger at one end and two of 4 terminals at the other end. The plunger is at the brake pedal’s end and the contacts are on the opposite side. Inside a brake light switch, you literally have a switch.
How to tell if a brake light switch is faulty?
- Place the vehicle in park or neutral with the emergency brake set. Raise the hood and disconnect the negative battery cable with a socket and wrench.
- Twist the bulb locking ring on the back of the taillight housing and pull the bulb socket out of the case housing.
- Unclasp the wire jack connectors to the brake lights.
How do you adjust the brake light switch?
To adjust the brake light switch, first press the brake pedal down a few inches, then pull the switch plunger rod out of the switch toward the brake pedal arm, as far as you can without using excessive force. Next, return the brake pedal to the pedal stop position against…
How do you install a brake light switch?
To install: Thread the brake light switch into its mounting bracket until the threaded end of the switch contacts the pad on the brake pedal. Back off the switch one quarter turn to allow 0.01 in (0.30mm) of clearance between the threaded portion of the switch and the pedal pad. Attach the brake light switch electrical connector.
Why are brake lights staying on?
If your brake lights are staying on, it will drain your battery. You need to disconnect your battery while the car is off or until you resolve this issue. The most likely cause for the brake lights staying on is the brake light switch sticking closed.