What are the causes of BYD S7 transmission failure?
2 Answers
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.
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.
