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Home >> Ford >> 2004 >> Thunderbird >> Repair and Diagnosis >> External Pages >> Different car >> Section 238 (Climate Control System) >> Diagnosis And Testing >> Climate Control System >> Symptom Chart
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Symptom Chart

WARNING: This page is about a different car, the 2003 Ford Thunderbird. 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.
 Go To PINPOINT TEST A .
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.
 Go To PINPOINT TEST B .
Incorrect/erratic direction of airflow from outlets
  • Circuitry.
  • Door actuator.
  • Airflow door binding or stuck.
  • DATC module.
  • Door actuator arm not connected to the door crank.
 Go To PINPOINT TEST C .
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.
  • Evaporator discharge air temperature sensor.
 Go To PINPOINT TEST H .
Insufficient heat during engine idle
  • Low engine coolant level.
  • Cold engine.
  • Bypass door actuator binding or stuck.
  • Auxiliary coolant pump.
  • Engine coolant thermostat.
 Go To PINPOINT TEST I .
Full heat only in all modes
  • Fuse(s).
  • Circuitry.
  • Coolant control valve.
  • DATC module.
  • Evaporator discharge air temperature sensor.
 Go To PINPOINT TEST J .
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.
 Go To PINPOINT TEST K .
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.
 Go To PINPOINT TEST L .
The air conditioning (A/C) is always on
  • Circuitry.
  • A/C control.
  • A/C clutch relay.
  • Evaporator air discharge sensor.
  • DATC module.
  • PCM.
 Go To PINPOINT TEST M .
The blower motor is inoperative
  • Circuitry.
  • Blower motor.
  • Blower motor speed control.
  • Blower motor relay.
  • DATC module.
 Go To PINPOINT TEST N .
The blower motor does not operate correctly
  • Blower motor speed control.
  • DATC module.
  • Circuitry.
 Go To PINPOINT TEST O .
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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