Ford F150 Pickup. Manual - part 1661

Fig. 3: Identifying Control Components Location - EATC (1 Of 2) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 HVAC Control Components - F150 Pickup

  

Fig. 4: Identifying Control Components Location - EATC (2 Of 2) 
Courtesy of FORD MOTOR CO. 

Manual Climate Control 

The manual climate control system heats or cools the vehicle interior depending on the function selector 
position and the temperature selected. Function selector position determines heating or cooling and air 
distribution. The temperature blend control setting determines air temperature. 

The manual climate control components are used to:

 

2003 Ford Pickup F150 

2003 HVAC Control Components - F150 Pickup

  

z

select air inlet source (outside or recirculated).  

z

select blower motor speed.  

z

select discharge air temperature (temperature blend).  

z

select discharge air location (defrost, panel, floor).  

z

select A/C compressor clutch operation.  

Manual Climate Control System Inputs 

Climate Control Assembly 

The climate control assembly has three system controls: 

z

The A/C heater function selector switch combines a vacuum selector valve with two electrical switches to 
supply battery positive voltage (B+) to the A/C clutch circuit and the blower motor control circuit.  

z

The temperature selection is accomplished with a potentiometer connected to the electric blend door 
actuator that controls positioning of the temperature blend door. Movement of the control knob from 
COOL (blue) to WARM (red) causes a corresponding movement on the air temperature control door and 
determines the temperature that the system will maintain.  

z

The blower motor switch controls blower motor speed by adding or bypassing resistors in the heater 
blower motor switch resistor.  

Manual Climate Control System Outputs 

Blower Motor Switch Resistor 

Blower Motor Resistor Coils 

 

2003 Ford Pickup F150 

2003 HVAC Control Components - F150 Pickup

  

Fig. 5: Locating Blower Motor Resistor Coils 
Courtesy of FORD MOTOR CO. 

Blower Motor Thermal Limiter 

 

2003 Ford Pickup F150 

2003 HVAC Control Components - F150 Pickup