Troubleshooting Hints

Malfunction of the connector [joint connector (CAN1), A/C controller assembly (A/C-ECU) < vehicles with A/C > or heater control unit (A/C-ECU) < vehicles without A/C > connector improperly connected]
Malfunction of the wiring harness [open circuit between the A/C controller assembly (A/C-ECU) < vehicles with A/C > or heater control unit (A/C-ECU) < vehicles without A/C > connector and the joint connector (CAN1), power supply circuit to the A/C controller assembly (A/C-ECU) < vehicles with A/C > or heater control unit (A/C-ECU) < vehicles without A/C >]
Malfunction of the A/C controller assembly (A/C-ECU) < vehicles with A/C > or heater control unit (A/C-ECU) < vehicles without A/C >