Manual Temperature Control (MTC) System
The Manual Temperature Control (MTC) single zone heating-A/C system uses electrically operated controls. These controls provide the vehicle operator with a number of setting options to help control the climate and comfort within the vehicle.
The A/C-heater control (1) for the MTC single zone system allows one temperature setting for the entire vehicle. All controls are identified by International Standardization Organization (ISO) graphic symbols.
The MTC A/C-heater control and integral computer is located in the instrument panel and contains:
- a rotary control for fan speed selection and for turning the heating-A/C system on and off (2). This control also contains a push button function for recirculating the conditioned air. The control contains an indicator lamp that illuminates when the heating-A/C system is in recirculation mode.
- a rotary control for temperature control of the discharged air (3). This control also contains a push button function for turning the A/C system on and off. The control contains an indicator lamp that illuminates when the A/C system is in operation.
- a rotary control for mode control of the discharged air (4). This control also contains a push button function for turning the rear window defogger system on and off. The control contains an indicator lamp that illuminates when the rear window defogger system is in operation.
The MTC A/C-heater control is diagnosed using a scan tool. Refer to the DTC INDEX article .
Prior to replacing the A/C-heater control, check for any Diagnostic Trouble Codes (DTCs) related to the heating-A/C system and run the Actuator Calibration function using a scan tool to verify that the concern is not an air door calibration issue. Refer to STANDARD PROCEDURE .
The A/C-heater control cannot be adjusted or repaired and must be replaced if inoperative or damaged.