Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Electronic Manual Temperature Control (EMTC) System
The EMTC system heats or cools the vehicle depending on the control panel selection.
- The control panel selections determine heating or cooling, air distribution and enables blower motor operation.
- The temperature control setting determines the air temperature.
- The blower motor switch varies the blower motor speed.
- During A/C operation the system also reduces the relative humidity of the air.
The EMTC system operation is determined by the settings on the climate controls. To control the various functions, the EMTC system is composed of the following:
- HVAC module
- Blower motor resistor
- Defrost/panel/floor mode door actuator
- Air inlet mode door actuator
- Temperature blend door actuator
- Evaporator temperature sensor
- Ambient air temperature sensor
The blower motor switch:
- sets the blower motor speed.
- is serviced only with the HVAC module.
The A/C request button:
- can command the A/C compressor ON when the function selector switch is in PANEL, FLOOR/PANEL, FLOOR/DEFROST and FLOOR when the A/C request switch is pressed. Indicator illuminates when A/C request switch is toggled ON.
- indicator illuminates when the function selector switch is in MAX A/C and cannot be toggled.
- is serviced only with the HVAC module.
The function selector:
- selects airflow direction.
- is serviced only with the HVAC module.
The temperature selector:
- selects full warm and full cool as well as blended outlet temperatures.
- is serviced only with the HVAC module.
The air recirculation button:
- selects either recirculated or outside air source.
- recirculates air in any mode except DEFROST, if requested.
- is disabled in MAX A/C or OFF mode where recirculated air only is used.
- is disabled in DEFROST mode where outside air only is used.
- is serviced only with the HVAC module.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.