This mode employs a radar sensor to detect the presence of vehicles up to approximately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle following distance, and operates to maintain a suitable following distance from the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long downhill slopes.

Approach warning warns you when the system cannot decelerate sufficiently to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by system control). After the vehicle ahead starts off, pushing the cruise control lever up or depressing the accelerator pedal will resume follow- up cruising.
Summary of functions
Setting the vehicle speed (vehicle-to-vehicle distance control mode)Toyota CH-R Service Manual > Air Conditioning System(for Automatic Air Conditioning System With Top-mounted
Air Conditioner Pressure Sensor): How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT
HINT:
Use the following procedure to troubleshoot the air conditioning system.
*: Use the Techstream.
PROCEDURE
1.
VEHICLE BROUGHT TO WORKSHOP
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Toyota CH-R Service Manual > Blind Spot Monitor System: Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
Blind Spot Monitor System
DTC No.
Detection Item
Link
C1A45
Vehicle Speed Sensor
C1A46
Yaw Rate Sensor
C1A47
St ...