What does it mean when the BYD Song transmission function is restricted?
3 Answers
This is the transmission's protection mode. When the transmission computer detects a transmission fault, it will protect the automatic transmission by locking it in a certain gear to reduce damage. Usually, the fault is caused by the transmission hydraulic control unit, which requires disassembling the transmission hydraulic control unit, i.e., the transmission's computer and valve body. Below is additional information: BYD Song: The dual-clutch transmission in the BYD Song controls the engine speed quite well. In D mode, it shifts up at 2000rpm to achieve the best fuel economy. To save even more fuel, you can switch the transmission to ECO mode, which slightly compromises performance but improves fuel economy.
Transmission function limitation on the BYD Song refers to partial restrictions on the operation of the transmission system, which may manifest as sluggish gear shifting, inability to engage high gears, or failure in electric mode switching. This typically occurs when the electronic control unit (ECU) detects anomalies and activates a protection program to prevent further damage. Common causes include sensor data deviation, excessively high transmission fluid temperature, software malfunctions, or wear and tear of mechanical components. From my personal experience, such issues are more likely to occur in high-mileage vehicles or after aggressive driving. During diagnosis, one can observe the warning lights on the dashboard and use an OBD scanner to read error codes for preliminary assessment. However, given the complex structure of BYD's hybrid transmission, it is advisable to visit a 4S store promptly for software updates and a comprehensive inspection. Regular maintenance is crucial; changing the transmission fluid every two years can reduce the likelihood of such failures by ensuring proper lubrication and cooling. Ignoring these warnings may lead to degraded driving performance or even breakdowns, so timely action is essential.
As an ordinary car owner, my BYD Song also once displayed a transmission function restricted warning. At that time, the car's acceleration became sluggish, and gear shifts were not smooth, meaning the transmission was locked in certain functions, possibly stuck in a low gear to prevent loss of control. Common triggers include frequent stop-and-go traffic leading to overheating, or sensor false alarms during cold starts. I immediately pulled over to check the vehicle, not daring to force driving to avoid complete transmission damage. Later, I went to the repair shop where the technician checked the fluid and circuits, then resolved the issue by upgrading the system software. Such problems are not difficult to fix, but safety-related issues should not be ignored; BYD's after-sales service can usually handle them quickly, and new cars under warranty get free treatment, which is more worry-free. In daily use, avoid driving for long periods in high-temperature environments and sudden acceleration to reduce the probability of occurrence.
