Volvo v50 2006 有防止引擎低速强制降档功能, 但没有写上面功能:
Volvo v50 2006 manual (pg. 112): While driving If you select the "M"
- If you hold the gear selector toward "-", the transmission will downshift one gear at a time and will utilize the braking power of the engine. If the current speed is too high for using a lower gear, the downshift will not occur until the speed has decreased enough to allow the lower gear to be used.
If you slow to a very low speed, the transmission will automatically shift down.