What are the causes of BYD S7 transmission failure?

[Tyrone]

BYD S7 transmission failure causes: There may be a fault in the power electronic control system, possibly due to a faulty connection line of a transmission sensor; lack of automatic transmission fluid; automatic transmission overheating or failure to increase speed due to one-way clutch slippage, etc. Functions of the transmission: 1. Change the transmission ratio: Meet the traction needs under different driving conditions, allowing the engine to operate as much as possible under favorable conditions and meet possible driving speed requirements. 2. Achieve reverse driving: Used to meet the needs of reverse driving. The engine crankshaft generally only rotates in one direction, but the car sometimes needs to reverse, so the reverse gear set in the transmission is often used to achieve reverse driving. 3. Interrupt power transmission: When the engine starts, idles, shifts gears, or needs to stop for power output, interrupt the power transmission to the drive wheels. 4. Achieve neutral gear: When the clutch is engaged, the transmission can output no power. For example, it ensures that the driver can release the clutch pedal and leave the driver's seat without the engine stalling.

[StIker]

As a car enthusiast, BYD S7 transmission failures are often related to the dual-clutch design. Frequent clutch plate wear in urban traffic congestion can lead to noticeable gear shift jerking; unstable hydraulic system oil pressure or leaks are also common, affecting shift smoothness; software bugs in the electronic control module can sometimes cause logic confusion, such as failure to upshift or downshift sticking. I found that regular transmission fluid checks are a key preventive measure, with the official recommendation to replace it every 40,000 kilometers. Using high-viscosity oil can reduce friction damage. In terms of driving habits, avoid sudden acceleration and prolonged low-speed driving to prevent overheating warnings. If early symptoms like unusual noises or vibrations are ignored, repair costs can skyrocket, so it's best to get a timely diagnosis at a 4S shop—spending a little now can save big on safety later.

[White]

I've been driving a BYD S7 for nearly three years and encountered a transmission issue where gear shifting was rough, especially with severe body shaking during acceleration. The dealership inspection revealed it was caused by worn clutch plates and insufficient fluid. Many owners in car groups complain about similar problems, with some cases resolved through software updates. However, my situation improved only after replacing the fluid and parts. I recommend avoiding frequent stop-and-go driving in congested areas as it increases wear. Always monitor fluid levels and quality during maintenance – neglecting this can lead to repair costs exceeding thousands. From experience, address minor symptoms promptly to prevent them from escalating into a full assembly replacement.

[MacJocelyn]

Untimely maintenance is a major cause of transmission failures in the BYD S7. The dual-clutch system is sensitive to fluid conditions, and insufficient lubrication due to contamination can easily lead to wear or slippage. I adhere to changing the specialized oil every 60,000 kilometers, effectively preventing issues. Some owners neglect maintenance, resulting in jerky gear shifts and repair costs several times higher than regular maintenance. Developing a habit of checking oil levels ensures peace of mind and safety.