How to Troubleshoot the Adaptive Cruise Control (ACC)
ACC Indicator (Amber)
When the ACC system detects a problem while operating, the ACC system stops working, and the ACC activation indicator (white) go off, then ACC indicator (amber) stays on.

NOTE: The ACC system communicates with the PCM, the VSA modulator-control unit, and the gauge control module via F-CAN. If a connected unit malfunctions, the ACC system will not operate. In this case, both the ACC indicator and the connected unit indicator come on and stay on (except the gauge control module).

ACC Activation Indicator (White)
When the ACC system is OK, the indicator comes on when the MAIN switch is ON, and goes off when the MAIN switch is OFF. If the ACC system detects any malfunctions, the ACC activation indicator (white) go off, then ACC indicator (amber) stays on.
Self-Diagnostic Function
The ACC system has a self-diagnostic function. If the self-diagnostic function detects a malfunction, the ACC system stops working, turns on the ACC indicator (amber), and stores DTCs.
Multi-Information Display (MID) Indication
When the ACC system is OK, the ACC indicates its status on the multi-information display (MID) when the MAIN switch is ON.
Dirt or Dust Detective Function
If the millimeter wave radar surface gets covered with too much debris or dirt, the multi-information display (MID) will display this icon (A), and the ACC system will cancel its function. Check the millimeter wave radar surface for debris or dirt.

Multipurpose Camera Unit
The multipurpose camera unit uses inputs from the millimeter wave radar to maintain a constant distance between your vehicle and the vehicle directly ahead by accelerating and braking as needed.
Millimeter Wave Radar
The millimeter wave radar measures the distance between your vehicle and the vehicle directly ahead to calculate and adjust speed to maintain the set distance between your vehicle and the vehicle ahead.

The multipurpose camera unit receives this information from the millimeter wave radar.

The millimeter wave radar also has an error detection function which sends a signal to the multipurpose camera unit if an error is detected.
CAN Communication
The multipurpose camera unit communicates on the F-CAN, and it communicates with other units via the F-CAN (gauge control module, steering angle sensor, PCM, SRS unit, and VSA modulator-control unit).

If the multipurpose camera unit detects a communication error or a malfunction in another connected unit, the ACC system will not operate even though it is OK. In this case, both the ACC indicator (amber) and the related unit indicator will come on and stay on.
Millimeter Wave Radar Aiming
If the millimeter wave radar is removed or replaced, you must do the millimeter wave radar aiming procedure, otherwise the ACC indicator (amber) comes on.
How to Troubleshoot DTCs
Check for DTCs with the HDS. Make a copy of the freeze data, then clear the DTC.

Before troubleshooting, check and note these items:
Ask the customer about the conditions when the problem occurred, and try to reproduce the same conditions for troubleshooting.
If the symptom does not appear and the ACC indicator does not come on during the test-drive of the vehicle, but if troubleshooting is done based on a DTC, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting.
After troubleshooting or repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions as when the DTC was originally set. Make sure the ACC indicator does not come on.
The ACC system sometimes stops working because of certain environmental conditions (weather, road conditions, driving conditions, etc.).
DTC may be stored even when the system is OK:
NOTE: The ACC indicator does not come on when DTC U3000-51: Multipurpose Camera Unit Update Incomplete is stored.
DTC B2A00-F8: Adaptive Cruise Control (ACC) Brake Control Temporarily Prohibited
The ACC brake works continuously, or ACC brake control is temporarily prohibited by a communication line error detected between the multipurpose camera unit and VSA modulator-control unit.
Intermittent Failures
The term ‘‘intermittent failure’’ means a system may have had a failure, but it checks OK now. If you cannot reproduce the condition, check for poor connections or loose terminals. Also check ground and power connections related to the circuit that you are troubleshooting.
How to Retrieve DTCs
NOTE: Make sure the 12 volt battery is fully charged before you begin.

1.

2.
Use the HDS to check for ACC DTCs.

3.
Read and record the DTC.

Freeze data records the ACC conditions when the first system malfunction that activated the indicator was detected.
The HDS can read the DTC, the freeze data, the current data, and other system data.

4.
Turn the vehicle to the OFF (LOCK) mode.

5.
Disconnect the HDS from the DLC.

6.
Do the troubleshooting procedure for the DTC.
How to Clear DTCs
NOTE: Make sure the 12 volt battery is fully charged before you begin.

1.

2.
In the DRIVING SUPPORT MENU of the HDS, select Integrated Driver Support System, then DTCs choose the clear DTCs icon, and follow the prompts.

3.
Turn the vehicle to the OFF (LOCK) mode.

4.
Disconnect the HDS from the DLC.
How to Read History of the System Auto Stop Control Code
NOTE: Make sure the 12 volt battery is fully charged before you begin.

1.

2.
In the DRIVING SUPPORT MENU of the HDS, select DATA LIST.

3.
Read and record the auto stop control code in the DATA LIST.

NOTE:
ACC system auto stop control history is recorded from 1. When automatic cancellation takes place 11 times or more, the past 10 records are held. In this case, history 10 is the latest record and the 10 latest records are held. When 0, no record is held.
When DTCs are cleared by the HDS, ACC system auto stop control history is cleared as well.
Some of the following ACC system auto stop control codes may not be used for specific model specifications.
ACC System Auto Stop Control Codes
Code
ACC system auto stops operating
ACC Indicator
Also check for
82
Adaptive cruise control (ACC) brake control temporarily prohibited by Electric Parking Brake
?
The ACC brake works continuously, or ACC brake control is temporarily prohibited by a communication line error detected between the multipurpose camera unit and electric parking brake control unit.
83
Radar detection unstable
?
Driving behind a target vehicle that caused unstable reception.
84
Target vehicle comes closer than the radar detecting limits
?
The target vehicle brakes suddenly, etc.
85
Extensive driving on a rough or winding road
?
Extensive driving on a rough or winding road.
86
Abnormal tire pressure
?
Abnormal tire pressure, flat tire.
87
Adaptive cruise control (ACC) brake control temporarily prohibited by VSA
?
The ACC brake works continuously, or ACC brake control is temporarily prohibited by a communication line error detected between the multipurpose camera unit and VSA modulator-control unit.
88*
Radar temporary problem (temperature, voltage, etc)
?
The millimeter wave radar temperature is too high, the millimeter wave radar supply voltage is too low, or out of detection condition.
89
Front wheel spin
?
Front wheel spin when the vehicle is driving.
91
Vehicle skidded, spun out, or abrupt steering wheel movements
?
Vehicle skidded, spun out, or abrupt steering wheel movements.
93
Front tire problem
?
Different diameter tires, flat tire, or large air pressure differential.
94
Rear tire problem
?
Different diameter tires, flat tire, or large air pressure differential.
95*
Power supply voltage too high
?
Battery voltage
96*
Power supply voltage too low
?
Battery voltage
97*
Extensive driving on a rough or winding road. (CMBS/FCW)
?
Extensive driving on a rough road or turn the vehicle to the OFF (LOCK) mode when the vehicle is driving.
98
Multipurpose camera unit temperature too high
?
Parked under the blazing sun for a certain time.
99
Acceleration/deceleration abnormality
?
Detect the vehicle acceleration/deceleration abnormality.
101
Rear wheel locked
?
Driving with the parking brake applied, or the parking brake stuck.
108
Adaptive cruise control (ACC) brake control temporarily prohibited by ESB
?
The ACC brake works continuously, or ACC brake control is temporarily prohibited by a communication line error detected between the multipurpose camera unit and electric servo brake control unit.
127
i-DCD cannot receive traction request
?
After the DCT (the built-in motor type) shifted during the acceleration. (especially low speed).
140
Yaw rate sensor temporarily error (low voltage, etc.)
?
12 Volt battery deterioration.
*: While the code is detected, the CMBS operation stops temporarily.

4.
Turn the vehicle to the OFF (LOCK) mode.

5.
Disconnect the HDS from the DLC.