2003 Ford Windstar BaseFACTORY OEM SERVICE PROCEDURE

Symptom Chart: Notes

WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
SYMPTOM CHART

Condition Possible Sources Action
  • No communication with the dual automatic temperature control (DATC) module
  • Fuse.
  • Circuitry.
  • DATC module communication network.
  • DATC module not connected.
  • The DATC system is inoperative, intermittent or incorrect operation
  • Circuitry.
  • Input sensors or erratic input signals.
  • Charging system.
  • In-vehicle temperature control sensor hose and elbow (No aspiration).
  • Air trapped in heater coolant circuits.
  • Missing or invalid SCP messages.
  • Incorrect/erratic direction of airflow from outlets
  • Circuitry.
  • Door actuator.
  • Mode door binding or stuck.
  • DATC module.
  • Door actuator arm not connected to the door crank.
  • Insufficient, erratic, or no heat
  • Circuitry.
  • Low engine coolant level.
  • Air trapped in heater coolant circuit.
  • Plugged or partially plugged heater core.
  • Bypass door actuator binding or stuck open.
  • Coolant control valve.
  • DATC module.
  • Engine coolant thermostat.
  • Insufficient heat during engine idle - 3.9L Engine
  • Low engine coolant level.
  • Cold engine.
  • Bypass door actuator binding or stuck.
  • Auxiliary coolant pump (V8 only).
  • Engine coolant thermostat.
  • Full heat only in all modes
  • Fuse(s).
  • Circuitry.
  • Coolant control valve.
  • DATC module.
  • The dual temperature control is inoperative/does not operate correctly
  • Circuitry.
  • DATC module configuration.
  • DATC module.
  • Coolant control valve.
  • Low coolant level.
  • Air trapped in coolant circuit.
  • Incorrect heater hose connections.
  • Air temperature sensors.
  • The air conditioning (A/C) is inoperative/does not operate correctly
  • Fuse(s).
  • Circuitry.
  • A/C clutch relay.
  • Evaporator discharge temperature sensor.
  • A/C system discharged or low charge.
  • A/C pressure transducer.
  • DATC module.
  • PCM.
  • The air conditioning (A/C) is always on
  • Circuitry.
  • A/C control.
  • A/C clutch relay.
  • Evaporator air discharge sensor.
  • DATC module.
  • PCM
  • The blower motor is inoperative
  • Circuitry.
  • Blower motor.
  • Blower motor speed control.
  • Blower motor relay.
  • DATC module.
  • The blower motor does not operate correctly
  • Blower motor speed control.
  • DATC module.
  • Circuitry.
  • The temperature set point does not repeat after turning the ignition switch off
  • Fuse.
  • Circuitry.
  • DATC module.
  • CHECK circuit 29-FA10 (OG/GN) for an open and repair as necessary. If okay, INSTALL a new DATC module.
  • The temperature display will not switch between Celsius and Fahrenheit
  • DATC module.
  • INSTALL a new DATC module. TEST the system for normal operation.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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