Adaptive Cruise Control/LKAS System Troubleshooting

Adaptive Cruise Control (ACC)/LKAS System Troubleshooting NOTE Retrieve DTCs, using the HDS. The adaptive cruise control (ACC)/LKAS system consists of the LKAS control unit, adaptive cruise control (ACC), a LKAS camera and the EPS (LKAS) control unit. Depending on the trouble that has been occurred, each unit or the camera individually writes in DTCs. Thus, when a trouble occurs, determine which unit writes these DTCs at first, and then starts diagnosing the trouble from the units or the camera the DTCs are coming from. Align the front wheels straight ahead. Turn the ignition switch OFF. Connect the HDS to the data link connector (DLC) (A). Turn the ignition switch ON (II). NOTE: See the HDS Help menu for specific instructions. Watch the adaptive cruise control (ACC)/LKAS indicator. Does the adaptive cruise control (ACC)/LKAS indicator come on?
YES | - | Go to Step 6 .
NO | - | Go to Step 8 .
Make sure the HDS communicates with the adaptive cruise control (ACC) unit. Is there communication?
YES | - | Go to Step 7 .
NO | - | Go to Step 18 .
Make sure the HDS communicates with the LKAS control unit. Is there communication?
YES | - | Go to Step 8 .
NO | - | Go to Step 21 .
Check for DTCs in the adaptive cruise control (ACC) unit DTCs MANU with the HDS. Is DTC 70 indicated?
YES | - | Go to Step 9 .
NO | - | Troubleshoot the adaptive cruise control (ACC) unit.■
Watch the adaptive cruise control (ACC)/LKAS indicator. Does the adaptive cruise control (ACC)/LKAS indicator come on?
YES | - | Go to Step 10 .
NO | - | Go to Step 16 .
Check for DTCs in the LKAS control unit DTCs MANU with the HDS. Is DTC 3, 4, 27, or 29 indicated?
YES | - | Perform the appropriate troubleshooting for the all cords indicated.■
NO | - | Go to Step 11 .
Clear the LKAS control unit DTCs using the HDS. Turn the ignition switch OFF, then turn it ON (II). Watch the adaptive cruise control (ACC)/LKAS indicator. Does the adaptive cruise control (ACC)/LKAS indicator come on?
YES | - | Go to Step 14 .
NO | - | Intermittent failure, the system is OK at this time. Go to Step 11 .
Check for DTCs in the LKAS control unit DTCs MANU with the HDS. Is DTC 20 indicated?
YES | - | Troubleshoot the EPS (LKAS) control unit DTCs.■
NO | - | Go to Step 15 .
Check for DTCs in the LKAS control unit DTCs MANU with the HDS. Is DTC 26 indicated?
YES | - | Troubleshoot the LKAS camera DTCs.■
NO | - | Troubleshoot the LKAS control unit DTCs.■
Clear the DTC using the HDS, and make sure the DTCs is not left. Turn the ignition switch OFF, and disconnect the HDS from the data link connector (DLC). Check the No. 31 (7.5 A) fuse in the under-dash fuse/relay box. Is the fuse OK?
YES | - | Go to Step 19 .
NO | - | Repair short to body ground in the wire between No. 31 (7.5 A) fuse and adaptive cruise control (ACC) unit.■
Turn the ignition switch ON (II). |

Measure the voltage between adaptive cruise control (ACC) unit 20P connector terminal No. 2 and body ground. Is there battery voltage?
YES | - | Troubleshoot the adaptive cruise control (ACC)/LKAS (orange) indicator does not go off in the adaptive cruise control (ACC) system. ■
NO | - | Repair open in the wire between the No. 29 (7.5 A) fuse and adaptive cruise control (ACC) unit.■ Faulty the LKAS relay.■
Turn the ignition switch OFF. Check the No. 31 (7.5 A) fuse in the under-dash fuse/relay box. Is the fuse OK?
YES | - | Go to Step 23 .
NO | - | Repair short to body ground in the wire between No. 31 (7.5 A) fuse and LKAS control unit.■
Turn the ignition switch ON (II). |

Measure the voltage between body ground and LKAS control unit 26P connector terminal No. 1 and No. 14 individually. Is there battery voltage?
YES | - | Go to Step 25 .
NO | - | Repair open in the wire between the No. 29 (7.5 A) fuse and adaptive cruise control (ACC) unit.■ Faulty the LKAS relay.■
Turn the ignition switch OFF. |

Check for continuity between body ground and LKAS control unit 26P connector terminal No. 13 and No. 26 individually. Is the fuse OK?
YES | - | Troubleshoot the adaptive cruise control (ACC)/LKAS (orange) indicator does not go off in the adaptive cruise control (ACC) system. ■
NO | - | Repair open in the wire between LKAS control unit and body ground (G501).■