Why can't the steering wheel turn when stepping on the brake?
3 Answers
When the steering wheel can't turn while stepping on the brake, it is caused by excessive internal leakage in the power steering pump. When the brake is applied, the engine speed suddenly drops. Due to the excessive internal leakage in the power steering pump, the pressure generated by the pump is insufficient to drive the steering cylinder, resulting in the steering wheel being difficult or impossible to turn. Methods to unlock a locked steering wheel in an electric vehicle: 1. If the key cannot be turned after insertion: The main reason the key cannot be turned is that the steering wheel was not properly aligned when the car was last parked, causing the steering wheel to lock abnormally. In this case, while gently turning the key with your right hand, wiggle the steering wheel left and right with your left hand, and the key can then be turned. 2. If the key cannot be removed after turning off the engine: This issue occurs in automatic transmission vehicles. The reason is that the gear shift lever in the P position is not fully engaged. Sometimes it may appear to be in place but does not trigger the electronic sensor, or there may be coins or other objects blocking the gear slot. 3. Check if there are any obstructions in the gear slot: Remove any obstructions, start the car, and shift the gear again to ensure it is fully engaged, then the key can be removed.
I encountered this issue when driving my old car. When I stepped on the brakes, the steering wheel felt like it was locked and wouldn't turn at all, which was really scary, especially during turns. This is usually caused by a failure in the brake assist system—possibly due to a leak in the vacuum booster or a loose belt—resulting in insufficient brake assist, which also affects the steering system. If this happens suddenly while driving, stay calm, slowly pull over, and check if the brake fluid level is normal. If it's low or appears dirty, it may indicate a leak. Also, listen for any unusual noises when braking. Never force the car to keep driving, as it could lead to an accident. I recommend going to a repair shop for a thorough inspection. After I got mine fixed, I also had the power steering fluid replaced, and the car ran much smoother afterward.
I noticed that the steering wheel becomes stiff when I step on the brake, which might be an issue with the linkage between the braking and steering systems. If the brake booster is leaking air or the valve is clogged, it can rob the power steering of its assist during braking, causing the steering wheel to lock up. I encountered a similar situation when driving a friend's car, and later inspection revealed that a hose in the booster system had aged and cracked, causing unstable vacuum pressure during braking. You can pop the hood yourself and listen for any hissing sounds indicating air leaks or check if the belt is loose and slack. However, this is quite technical, and I wouldn't recommend beginners to tamper with it. It's best to take the car to a dealership for inspection as soon as possible to prevent minor issues from turning into major problems. Also, make sure to regularly maintain the brake components.
