What are the causes of the HAVAL H6 hill descent control failure?
2 Answers
HAVAL H6 hill descent control failure reasons are as follows: 1. Fault in PT-CAN related wiring or a certain node: Using a fault detection device, it was found that the electronic parking brake control module (EPB) stored one current fault code: "U111281 ESP CAN signal failure." The electronic stability program control module (ESP) also stored one current fault code: "U100104 CAN passive error." The engine control module (ECM) stored two historical fault codes: "U01018 Communication with TCU" and "U012687 Lost communication with SAS"; no fault codes were stored in other modules. Analyzing the fault codes, it is inferred that there is a fault in the PT-CAN related wiring or a certain node. 2. Virtual connection in the gateway internal circuit leading to low network voltage: When HDC is set and the vehicle enters a steep slope, engine braking itself can provide a considerable degree of deceleration effect without the risk of tire lockup. When the steep slope gradient is too large and engine braking is insufficient to maintain the speed limit, HDC can use the ABS system to reduce the gradually increasing speed, maintaining a stable and safe speed downhill. If the driver needs to steer to avoid obstacles during the steep descent, the HDC system will detect this and further reduce the speed limit to 6.4 km/h to ensure complete vehicle control.
I've encountered the Hill Descent Control (HDC) malfunction issue with the Haval H6 several times. From what I understand, the problem mostly lies in the electronic control system. When sensors like the wheel speed sensor or gradient sensor get dirty or damaged, causing abnormal signal transmission, the system fails to recognize steep slopes. If the Electronic Control Unit (ECU) has bugs and sends incorrect commands, it can make the brake module respond sluggishly. Loose wiring connections, especially when short-circuited by water ingress during rainy days, can directly disable the function. There are also issues with the brake hydraulic system, such as low fluid levels or air bubbles, which affect control effectiveness. I recommend regularly checking these components to prevent minor issues from escalating. When a malfunction occurs, avoid descending steep slopes hastily—using manual braking is safer. It's best to visit a 4S shop immediately for a comprehensive scan; software updates often help. Since this function relies on the ABS system, related faults should also be checked. Regular maintenance of the vehicle's undercarriage to prevent dust and moisture buildup can significantly improve overall condition.
