2005 Lexus GX 470 Owners Manual - Page 461

STARTING AND DRIVING D The warning light comes on while driving. Turning on the system 1. Shift the four-wheel drive control lever to the "L" position. The system will not operate if the four-wheel drive control lever is in the "H" position. 2. In order to make full use of the engine brake, putting the transmission in "L" or "2" is recommended. The system will operate even if the transmission selector lever is in "D", "4", "3" or "N". However, when it is in "L" or "2" the engine brake can also be utilized enabling the system to operate more effectively. DOWNHILL ASSIST CONTROL SYSTEM The downhill assist control system is a system that assists the deceleration of the engine brake when you drive down a steep hill. When you are driving down a hill with the four-wheel drive control lever in the "L" position, push the "DAC" switch to limit the vehicle's acceleration. If the vehicle is traveling at a speed of 25 km/h (15 mph) or less, you can descend at a constant speed. CAUTION Do not rely excessively on the downhill assist control system. It may not be able to maintain a low speed over road surfaces or off-road surfaces on which sliding can easily occur, such as extremely steep slopes or icy or muddy roads. 3. Push the "DAC" switch to turn the system on. The downhill assist control system indicator light on the instrument panel will come on. 436