1. Check for voltage between the adaptive cruise control (ACC) unit 20P connector No. 17 terminal and body ground.

Is there battery voltage?

YES | - | Repair an open in the wire between the adaptive cruise control (ACC) unit and the millimeter wave radar unit.■
NO | - | Check for loose or poor connections. If OK, replace the adaptive cruise control (ACC) unit , then go to Step 18 .

1. Turn the ignition switch OFF.

1. Disconnect the 20P connector from the adaptive cruise control (ACC) unit.