Why can't the car start in P gear but can start in N gear?

[PaisleeFitz]

The reason why the car can't start in P gear but can start in N gear is that the P gear does not return to its proper position. Reasons for P gear not returning to position: The P gear locking mechanism is stuck and cannot return to position. The shift solenoid is damaged and cannot complete the shift command. The gear shift cable is damaged or broken. The control computer is faulty. The P gear locking mechanism in the transmission consists of a locking gear, a locking pin, and a set of actuating mechanisms. Solutions for P gear not engaging: You can try unlocking the gear lock with a key. If it still doesn't work, check whether the brake lights are on when you press the brake pedal. If the brake lights do not turn on, the brake switch is faulty, and the car's computer cannot detect whether the brake is pressed, so it cannot shift gears.

[DelLiam]

I've been driving for almost thirty years, and I've personally experienced this issue. Back then, my old Ford wouldn't start at all in P gear, but it fired up easily when shifted to N gear. After struggling for several days, I finally discovered it was a problem with the gear position sensor. Automatic transmissions are designed for safety, requiring the system to recognize P or N gear before allowing ignition to prevent the car from moving unexpectedly during startup. If the sensor gets dusty or ages, it sends incorrect signals to the computer, leading to a misjudgment of the P gear signal. Just think about how dangerous it would be if the car suddenly started in P gear without properly pressing the brake. So, my advice is to first check the gear position switch if you encounter this situation—don't force it to avoid damaging the car. During regular maintenance, have the mechanic take a look at this component; a simple check can prevent major troubles.

[LeJake]

I've encountered a similar situation before. My Toyota wouldn't start in P gear, but it fired right up when shifted to neutral. After researching and consulting mechanics, I learned this is usually caused by a faulty gear position sensor. The vehicle's ignition system has a safety lock that only allows starting in Park or Neutral positions to prevent accidental acceleration when starting. If the P gear signal isn't properly transmitted to the control system, the ignition will be denied. You might try gently wiggling the gearshift lever to see if it triggers a response - it could just be poor contact. In the long run, replacing a small component should fix it. Experienced drivers know these minor issues can be really troublesome, especially on winter mornings when you're in a hurry to leave, so it's best to get it repaired promptly.

[ElizabethMarie]

This common issue stems from the safety mechanism of automatic transmissions. The vehicle requires the gear to be in P or N position to start, preventing rolling during ignition. If the car won't start in P but works in N, it's often caused by a faulty gear position sensor failing to send P gear signals to the control system. Internal sensor contacts may be oxidized or broken, causing misjudgment. We recommend inspecting the sensor and related circuits.