1998 Town car a/c

[lonestar tech]

I have a 98 town car and it will only blow hot air.

[Bearfoot]

I have a 1955 wife and she only blows hot air!

[Towncar]

Originally Posted by Bearfoot

I have a 1955 wife and she only blows hot air!

Mines a 1958, same symptoms exactly


Lonestar Tech...
Put the system into self test mode, and see if there's any trouble codes stored... here's the method and code chart.


Electronic Automatic Temperature Control Module Self-Test

• The EATC module self-test will not detect concerns associated with data link messages like engine coolant temperature or vehicle speed signals. A NGS tester must be used to retrieve these concerns.
  
• The EATC module self-test will detect concerns in the system control functions and will display hard diagnostic trouble codes (DTCs) hard DTC's identify faults which are present during self test. The vehicle interior temperature should be between 4º-32ºC (40-90ºF) when carrying out the self-test. If the temperatures are not within the specified ranges, false in-car temperature sensor DTCs will be displayed.
  
• The self-test can be initiated at any time. Normal operation of the system stops when the self-test is activated.
  
• To enter the self-test, press the OFF and FLOOR buttons simultaneously and then press the AUTOMATIC button within two seconds. The display will show a pulse tracer going around the center of the display window. The test may run as long as 30 seconds. Record all DTCs displayed.
  
• If any DTCs appear during the self-test, follow the diagnostics procedure given under ACTION for each DTC given.
  
• If a condition exists but no DTCs appear during the self-test, refer to the Symptom Chart Condition: The EATC System Is Inoperative, Intermittent or Improper Operation.
  
• To exit the self-test and clear all DTCs, press the DEFROST button. The vacuum fluorescent display window will show 888 and all function symbols for one second. Then, the EATC control assembly will turn OFF (display blank) and all DTCs will be cleared.
  
• Always exit the self-test before powering the system down (system turned OFF).

Electronic Automatic Temperature Control of Continuous Codes

• This function will display intermittent and hard faults that occur during normal operation.
  
• Display continuous codes can be initiated at any time. Normal operation of the system stops when display continuous codes is activated. Note that "º C" will be displayed while in this mode.
  
• To enter continuous display, press the OFF and PANEL buttons simultaneously and then release and within two seconds press the AUTO button.
  
• To exit continuous displays, press FRONT DEFROST. This will exit and clear all DTCs. Press the floor button to exit without clearing DTCs set before the last ignition cycle.
  
• Always exit continuous display before powering the system down (system turned off).
  
• Intermittent DTCs are saved only after an ignition cycle.
  
• Intermittent DTCs will be deleted after 80 ignition switch ON cycles after the intermittent condition occurs.

< very sorry, I did have the wrong chart here, this is corrected >


This chart is for the codes retrieved using an OBDii Scanner:




Based on your initial findings, we can venture into the symptoms diagnosis listed in this index:

Symptom Chart

Condition(s):
o No communication with the electronic automatic temperature control module
o The EATC system is inoperative, intermittent or incorrect operation
o Incorrect/erratic direction of airflow from outlet
o Insufficient, erratic or no heat
o The A/C does not operate or does not operate correctly
o The A/C is always on
o Insufficient A/C cooling
o The blower motor does not operate
o The blower motor operates continuously only in high speed
o No operation in some blower settings
o The temperature set point does not repeat after turning the ignition switch off
o The temperature display will not switch between Celsius and Fahrenheit
o One or more steering wheel control switch is inoperative

[jissle]

I Did Mine And 24 Came Up Can U Help What Doesthat Mean

[Towncar]

Originally Posted by jissle

I Did Mine And 24 Came Up Can U Help What Doesthat Mean

# 024, Blend Door Actuator.

Basically, there's a small motor that controls the door position of the hot/cold blend of air. The unit is called an Actuator and it breaks. Unfortunately, the dashboard has to be partially removed to get at it.


Search these Town Car forums for Blend Door Actuator or Blend Door.
There's lots of information here on that one.

Here's one photo of the Blend Door Actuator Guts, from a MKVIII:

Courtesy of: http://mark8.org/lod/blend_door_reinforce.htm