See also:

When the VSC/TRAC or Active TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip- ping or rolling backward when starting on an incline, or if any of the drive wheels spins, the slip indi- cator light flashes to indicate that the VSC/TRAC or ...

Maintenance requirements
To ensure safe and economical driving, day-to-day care and regular maintenance is essential. It is the owner’s responsibility to perform regular checks. Lexus recommends the following maintenance. ...

DAC (Downhill Assist Control system)
The DAC helps to prevent excessive speed on steep downhill slopes. The system will operate when the vehicle is traveling under 15 mph (25 km/h) and the four-wheel drive control switch is in the L4 ...