The brakes of your car are essential to both safety and control, but they do much more than just stop the car. They also play a role in starting it up. This is why most cars require you to depress the brake pedal when you turn the key in the ignition and push the start button – for safety reasons, the computer needs to receive an electronic signal that the brakes are pressed before it will engage the starter circuit to get the engine running. If the brake pedal is stiff, the computer won’t receive that signal and the car will be difficult to start.
There are many things that can cause a stiff brake pedal, including air in the hydraulic system or dirt and grime built up on the pedal. In more severe cases, if the brake pedal is so hard that it can’t be depressed, you might have a broken brake light switch. This component sends an electrical signal to the brake lights when it is pressed, so if it becomes faulty, the system won’t be able to tell when you depress the brake pedal and the car won’t start.
There are other reasons that a car may not start, including a bad battery, a faulty starter motor, or a problem with the neutral safety switch or spark plug wires. These are more complex issues, and you’ll likely need to have a professional mechanic diagnose and repair the problem.