STEP 1. Check of open circuit, and short circuit in SOL+ line between electronic control coupling solenoid connector and AWC-ECU connector.
STEP 2. Check of open circuit, and short circuit in SOL- line between electronic control coupling solenoid connector and AWC-ECU connector.
STEP 3. Check of the electronic control coupling solenoid.
STEP 4. Check whether the DTC is set again.