What Causes an Automatic Transmission Car Not to Move When Reversing with the Steering Wheel Turned to Full Lock?
2 Answers
The reasons why an automatic transmission car does not move when reversing with the steering wheel turned to full lock may include accidentally pressing the auto-hold button, the electronic parking brake not being released, or transmission issues. The details are as follows: Accidentally Pressing the Auto-Hold Button: Enabling this function enhances safety when waiting at traffic lights or crossing pedestrian crossings by preventing the car from moving without pressing the accelerator. Once the auto-hold function is deactivated, releasing the brake will allow the car to move forward or reverse. Electronic Parking Brake Not Released or Incorrect Gear Engagement: If the electronic parking brake is not released or the gear is not properly engaged, the reverse gear may not function. Releasing the electronic parking brake and adjusting the gear engagement method can resolve this issue. Transmission Issues: Internal transmission failure may occur. First, check if the transmission fluid level is too low and whether the main oil pressure and gear oil pressure are normal. Then, verify if the gear position switch signal is correct, if the wiring from the transmission computer to the shift solenoid valve is intact, and if the gear solenoid valve is functioning properly. If all these checks show no issues, it indicates a problem with the internal control system of the transmission, requiring disassembly to inspect the internal components.
As someone who has been working in car maintenance for a long time, this is a very common issue. When an automatic transmission car doesn't move while reversing with the steering wheel fully turned, the main reason could be that the parking brake isn't fully released, causing the rear wheels to lock up and the brakes to seize. Turning the steering wheel to its limit significantly increases steering resistance, especially on slopes or uneven ground, where the engine's power is dragged down by tire friction, preventing movement. The torque converter in the transmission also can't fully engage the power under these conditions. Another factor could be issues with the brake system, such as rusted or frozen brake calipers or blocked brake lines. I recommend first checking if the handbrake is fully released and gently tapping the accelerator to see if the car moves. If that doesn't work, check for any foreign objects stuck in the tires or if the tire pressure is too low. From a design perspective, it's best to avoid holding the steering wheel fully turned for extended periods to reduce the load on the power steering pump, which can extend the lifespan of components. If you encounter this situation during daily driving, it's advisable to turn off the engine and restart it before trying again, or take the car to a professional shop to inspect the brake and transmission systems to prevent further damage.
