Adaptive Cruise Control (ACC) Symptom Troubleshooting Index
NOTE: The ACC system is cancelled when the VSA system is activated.

Symptom
Diagnostic procedure
Also check for
ACC indicator (amber) does not come on
Do the gauge control module self-diagnostic function.
  
ACC indicator (amber) does not go off
Symptom troubleshooting.
  
ACC OFF is displayed on the MID unexpectedly
Check the ACC system auto stop control history.
  
ACC combination switch does not work (ACC system is OK)
Symptom troubleshooting.
  
Vehicle speed can be set, but there is no ACC indication on the MID
Do the gauge control module self-diagnostic function.
  
Vehicle speed cannot be set when the SET switch is pressed (between the 25 mph (40 km/h) and 90 mph (145 km/h))
An open in the wire.
A short in the wire.
The system is in service mode.
Vehicle does not decelerate or accelerate accordingly when the SET or RESUME switch is pressed
Symptom troubleshooting.
An open in the wire.
Set speed does not cancel when the brake pedal is pressed
Test the brake pedal position switch.
An open in the wire.
Set speed does not cancel when the MAIN switch is turned off
Symptom troubleshooting.
An open in the wire.
Set distance cannot be adjusted with the distance switch
Symptom troubleshooting.
  
Vehicle speed can be set, but vehicle decelerates
Check for DTCs in the PGM-FI system with the HDS.
  
Senses a vehicle driving in another lane
Symptom troubleshooting.
Incorrect millimeter wave radar installation.
Wheel alignment.
Does not sense the vehicle driving ahead
Symptom troubleshooting.
Out of the performance limits.
Wheel alignment.
Undetectable environment.
Intermittently senses the vehicle driving ahead
Symptom troubleshooting.
Incorrect millimeter wave radar installation.
Wheel alignment.
Undetectable environment.