98 Mark VIII Climate Control Issue?

itlnrob

Registered
Hey guys, recently purchased a 98 Mark VIII almost mint with 41k miles. It's an awesome car, and the previous owner swapped out the air ride with the supercoupe suspension.

Anyways, the heat works fine in the car but when you put the fan speed to a low setting, it doesn't blow out as hot no matter what temperature you set the thermostat to....80, 85, 90 etc.

If you put the fan to about middle or high it comes out as hot as it should. I also noticed that the Automatic feature functions properly. What do you think this issue could be?

I did locate the wires going to the blower motor, and they seem to be snug and secured. The wires did not look burnt or fried. The blend door was actually replaced by the previous owner about 6 months ago.

I was thinking that it might be the actual climate control unit, but not sure.

Thanks for your help,

Rob
 

itlnrob

Registered
I did do the electronic self test.....seemed like it ran through its course and then after a while just showed all the lights on in the digital display portion. I hit the blue button and it reset.
 

BadSax

enjoys 3 martini lunches
I dunno... what color is your car?
The only solution maybe to give it to me... :D

:D -J
 

driller

El Presidente
Staff member
Well, remind us forgetful folks what buttons you press etc... :D

OK....

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 (DTC) in addition to intermittent diagnostic trouble codes for concerns that occur during system operation. The vehicle interior temperature should be between 4°-32°C (40-90°F) when performing 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 self-test and retain all intermittent DTCs, push the blue (cooler) button. The control will exit self-test, retain all intermittent diagnostic trouble codes and then turn OFF (display blank).
To exit self-test and clear all diagnostic trouble codes, 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).
 

billcu

Head Moderator
Staff member
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 (DTC) in addition to intermittent diagnostic trouble codes for concerns that occur during system operation. The vehicle interior temperature should be between 4°-32°C (40-90°F) when performing 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 self-test and retain all intermittent DTCs, push the blue (cooler) button. The control will exit self-test, retain all intermittent diagnostic trouble codes and then turn OFF (display blank).
To exit self-test and clear all diagnostic trouble codes, 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).


__________________
JP

Does this self test work on a Gen 2?

I tried it and it doesn't work on mine.
 

driller

El Presidente
Staff member
Does this self test work on a Gen 2?

I tried it and it doesn't work on mine.

For a Gen2...

Electronic Automatic Temperature Control Unit Self-Test

The EATC self-test will detect concerns in the system control functions and will display diagnostic trouble codes (DTC) in addition to intermittent diagnostic trouble codes for concerns that occur during system operation. The vehicle interior temperature should be between 16-26°C (60-80°F) when performing the self-test. If the temperatures are not within the specified ranges, false in-car temperature sensor DTCs will be displayed. 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: EATC System Inoperative, Intermittent or Improper Operation.

The self-test can be initiated at any time with any resulting DTCs displayed. 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.

To exit self-test and retain DTCs, push the blue (cooler) button. The control will exit self-test, retain all diagnostic trouble codes and then turn OFF (display blank).

To exit self-test and clear all diagnostic trouble codes, 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.

The self-test should be deactivated before powering the system down (system turned OFF). Intermittent DTCs will be deleted after 80 ignition switch ON cycles after the intermittent condition occurs.

Looks to be the same?
 

billcu

Head Moderator
Staff member
Looks to be the same?[/QUOTE]

Yes, that's the same sequence I tried.

It won't work on my car. It won't work on my green 94 with a 96 heater control either.

Anyone with a Gen 2 care to try it and report back?:D
 

budpytko

Registered
It didn't work for me either...BUT.... to be fair, the outside air temp[ was only 59*. The test requires 60 as a minumum. I'll try a little later if it warms up anymore.

I did not even get the "pulse" mark tho......
 
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billcu

Head Moderator
Staff member
Thanks Bud!

Let me know what you find.

I think even cold, the test should run.
 

budpytko

Registered
I never could make it run. I won't be home until Saturday. All my notes are there,,,I'll check the procedure again then and post results.
 

budpytko

Registered
My manual gives the same buttons to push for self-test. I can't get it to work.....Has anyone ever done it and if so, HOW?
 

J

OCCUPY LoD :)
I think it said something about attempting it while driving into a parking stall at a Chinese restaraunt.....OOOOHHHH! :D
 

budpytko

Registered
I think it said something about attempting it while driving into a parking stall at a Japanese restaurant.....OOOOHHHH! :D

I corrected it for you..... if you are gonna pick on me at least get the facts straight.
:fart
 
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