What causes the inability to press the brake pedal and start the car?
4 Answers
The inability to press the brake pedal and start the car is due to a malfunction in the brake pedal or the brake booster system. In automatic transmission vehicles, the engine requires the driver to press the brake pedal to start. If the brake pedal cannot be pressed, the engine will not start. If the brake light switch is damaged, pressing the brake pedal will not illuminate the brake lights; if the brake lights themselves are damaged, pressing the brake pedal will also fail to light them. In such cases, the vehicle's computer will determine that the driver has not pressed the brake pedal, preventing the engine from starting. To resolve this issue, simply replace the faulty brake light bulb or brake light switch. If the problem lies with the brake pedal or brake booster system, replacement of the brake pedal or brake booster pump will be necessary.
Once when I was about to drive out, I couldn't press the brake pedal and the car wouldn't start—what a headache. After checking, the main cause was likely an issue with the brake booster system. Most modern cars rely on a vacuum pump or electric motor to assist with braking. If this fails, the brake pedal becomes as hard as a rock and impossible to press. Sometimes electronic malfunctions can also cause trouble, such as faulty brake sensors or switches, making the car think you're not pressing the brake and preventing startup. An aging battery can also be the culprit—if the power is insufficient, the brake booster won't function, leading to startup failure. Additionally, leaking brake fluid or clogged lines can make the pedal stiff and unresponsive. For safety, call a tow truck and take it to a repair shop immediately—never force the car to drive, as it could cause damage or accidents. Regular maintenance and brake system checks can help prevent such issues.
When encountering a situation where the brake pedal is hard to press and the car won't start, I believe the primary causes lie in the power assist system or electrical circuit. From my experience, vacuum booster pump failure is the most common issue. It relies on the engine to create vacuum, and if it malfunctions, the brakes become harder to press and the car becomes difficult to start. On the electrical side, problems like a faulty brake switch or related wiring harness can trigger the modern car's anti-theft system, preventing startup. A depleted battery can also have a dual impact. Safety is the top concern, so it's recommended to stop using the vehicle immediately, check if the brake fluid is sufficient or if there's any leakage, and then test the battery voltage. If you're handy, you can perform a simple fuse check, but it's best to call a professional to prevent further damage. Regularly changing brake fluid and inspecting the electrical system are key preventive measures.
The brake pedal being hard to press and the car failing to start are often caused by mechanical or electronic interference. For instance, a faulty vacuum booster can't provide assistance, making the pedal feel extremely stiff. If the brake position sensor in the circuit malfunctions and fails to detect foot pressure, the engine won't respond. A weak battery can lead to insufficient power assistance and weak starting. Additionally, module failures such as a frozen computer can lock the system. From personal experience, it's advisable to first check the brake fluid level and battery health. If that doesn't resolve the issue, it's necessary to visit a repair shop for a comprehensive diagnosis to ensure safety.
