Pressing the button changes the vehicle-to-vehicle distance as follows:

The vehicle-to-vehicle distance is set automatically to long mode when the engine switch is turned to ignition on mode.
If a vehicle is running ahead of you, the preceding vehicle mark will also be displayed.
Vehicle-to-vehicle distance settings
Select a distance from the table below. Note that the distances shown correspond to a vehicle speed of 50 mph (80 km/h). Vehicle-to-vehicle distance increases/decreases in accordance with vehicle speed.

Adjusting the set speed
Canceling and resuming the speed controlInspection
1. COOLER THERMISTOR NO.1(MANUAL AIR CONDITIONER)
(a) Remove cooler thermistor No. 1.
(b) Check resistance between terminals 1 and 2 of cooler
thermistor No. 1 at each temperature, as shown in the
chart.
Standard:
NOTICE:
Even slightly touching the sensor may change the resistance
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