How to Solve the Problem of Car Descent Control Failure?
3 Answers
Car descent control failure can be solved by adding brake fluid or going to a 4S shop for detailed inspection. The car descent control function, also known as the hill descent control or HDC, allows the driver to smoothly pass steep downhill sections without stepping on the brake pedal. As needed, the braking device automatically controls each wheel to move forward at a speed slightly faster than walking, allowing the driver to fully focus on steering. When the HDC is set and the vehicle enters a steep slope, the engine brake itself can provide a certain deceleration effect. When the slope is too steep and the engine brake is insufficient to maintain the speed limit, the HDC can use the ABS system to start the brake point release when necessary, reducing the increasing speed to maintain a stable and safe downhill speed.
Last time when I encountered an issue with the hill descent control function, I first checked if the vehicle's ABS and brake system were functioning properly. Sometimes if the brake pads are worn or sensors are covered in dust, the system can malfunction. I tried restarting the engine, but the problem persisted, so I immediately drove to a professional repair shop. The technician said the control module's software needed an update - they spent some time reprogramming it and fixed the issue. Remember not to force this function on steep slopes when it's faulty, as the vehicle might suddenly accelerate downhill, which is very dangerous. In case of failure, pull over immediately, turn on hazard lights, and seek assistance. During regular maintenance, always ask technicians to inspect related electronic components, especially for owners who frequently drive in mountainous areas. Periodic maintenance can prevent most problems.
There can be many possible reasons for the failure of the hill descent control function, such as a faulty wheel speed sensor, an error in the electronic control unit, or an unsuitable ground slope. I think the simplest way is to start by checking the vehicle manual to see if there are any temporary shutdown recommendations. Try cleaning the mud around the sensor yourself. If that doesn't work, just make a trip to the 4S shop. They have specialized diagnostic tools to read fault codes. Don't randomly disconnect the battery cable to avoid accidentally triggering other warnings. Safety first—if there's a problem, stop driving on steep slopes and use low gear to manually control the downhill speed. Usually, avoid excessive use of the hill descent system on waterlogged or gravel roads. Tire tread wear also affects performance, so it's recommended to have a comprehensive check every six months.
