Audio Communication Line Circuit Troubleshooting
  1. Connect the center display unit 12P connector No. 7 and No. 8 terminals with a jumper wire.
  1. Turn the ignition switch to ON (II).
  1. Press and hold the DEF button and OFF button.
Is the DEF button LED blinking?
YES -
Center display unit is faulty, replace the center display unit.
NO -
Heater control unit is faulty, replace the heater control unit.