Adaptive Cruise Control Symptom Troubleshooting

NOTE: The adaptive cruise control system is cancelled when the VSA system is activated.

Symptom | Diagnostic procedure | Also check for
--- | --- | ---
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 40 km/h (25 mph) and 145 km/h (90 mph)) | 1. 2. 3. 4. | Test the adaptive cruise control (ACC) combination switch. Test the transmission range switch. Test the brake pedal position switch. Check for a short in the SCS line. |

- Blown No. 4 (15 A) or No. 13 (20 A) fuse in the under-hood fuse/relay box
- An open in the wire
- A short in the wire
- The system is in service mode

Vehicle speed does not decelerate or accelerate accordingly when the set/resume switch is pressed | Test the adaptive cruise control (ACC) combination switch. |

- An open in the wire
- A short in the wire

Set speed does not cancel when the shift lever is in position N | Test the transmission range switch. |

- An open in the wire
- A short 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
- A short in the wire

Set speed does not cancel when the adaptive cruise control (ACC) switch is turned off | Test the adaptive cruise control (ACC) combination switch. |

- An open in the wire
- A short in the wire

Set distance cannot be adjusted with the distance switch | Test the distance switch. |

- An open in the wire
- A short in the wire

Vehicle speed can be set, but vehicle speed decelerates | Check for DTCs in the PGM-FI system with the HDS. | Faulty ETCS
Senses a vehicle driving in another lane | Do the adaptive cruise control (ACC) system check. |

- Incorrect millimeter wave radar unit installation
- Wheel alignment

Does not sense the vehicle driving ahead | Do the adaptive cruise control (ACC) system check. |

- Out of the performance limits
- Wheel alignment
- Undetectable environment

Intermittently senses the vehicle driving ahead | Do the adaptive cruise control (ACC) system check. |

- Incorrect millimeter wave radar unit installation
- Wheel alignment
- Undetectable environment

Adaptive cruise control (ACC) indicator (orange) does not come on | Symptom Troubleshooting |
Adaptive cruise control (ACC) indicator (orange) does not go off | Symptom Troubleshooting |
Adaptive cruise control (ACC) activation indicator (green) does not come on | Symptom Troubleshooting |
Adaptive cruise control (ACC) activation indicator (green) does not go off | Symptom Troubleshooting |