STEP 1. Using scan tool (M.U.T.-IIISE), check data list.
STEP 2. Check the operation of the audio remote control switch.
STEP 3. Check of short to power supply, short to ground, and open circuit in REM+, REM- line between multivision display connector and steering wheel remote control switch connector.
STEP 4. Check the camera switch (steering wheel remote control switch).
STEP 5. Retest the system.