No Heat

[MMinMN]

So I was driving my car in -5 degree teperatures heat working fine and all. Then all of a sudden it started blowing cold air on my feet. Tried turning the climate control to manual operation which didn't change anything. Blower still works fine. Think this is a bad Temperature Blend Door Actuator, bad wires, vacuum line, or the EATC?

[ctrlraven]

I hope you at least have heated seats and it's nothing major.

[MMinMN]

no heated seats!

I have a Jaguar with heated seats, but that has a bad engine!

[Kelly]

Thermostat stuck open, try burping your system first.

[MMinMN]

Thermostat stuck open, burp your system first.

I doubt it's that as the air went to ICE cold very quickly. Almost seems more like the blend door changed when it was not suppose to. I'll give it a shot. Got any instructions on that?

[ctrlraven]

Use the search button, plenty of threads about it.

[Vortech347]

Just top off your cooling system. My 03' did that.

[RacerX]

It's probably the little O rings inside the EATC itself. Easy fix. See Sticky!
http://www.mercurymarauder.net/forums/showthread.php?t=36922

[ctrlraven]

He said it went to cold air not air directing towards the defroster. lol

As long as you can direct all of the air to whatever button you select VENT, FLOOR, FLOOR/DEFROST and it's only coming out that desired area it's not the EATC. Haven't seen anything talk about their EATC causing no heat but air still moving.

[MMinMN]

It was still coming out the floor when blowing cold. I'll have to still try and see if all the other functions work. I am thinking it's the blend door motor which would suck because it looks like the dash needs to come out to get to it!

[ctrlraven]

Double check the directional air functions to rule out the EATC.

[RacerX]

True that! Thermocoupler needs new bearings and a thermistor riser flange... :D

Isn't there a way to read codes from the EATC??? Thought I read that somewhere...

Oh yeah...

push the Off & Floor buttons together, then push Auto.
I am told, this is the same for all Fords, with ATC.

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) 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 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 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 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).
· Intermittent DTCs will be deleted after 80 ignition switch ON cycles after the intermittent condition occurs.
EATC Hard Self-Test Faults
EATC Intermittent Run-Time Faults
NGS DTC
Description
024
022
B1249
Blend door short

025
B1249
Blend door failure
031
N/A
B1251
A/C in-car temperature sensor open circuit
030
N/A
B1253
A/C in-car temperature sensor short to ground
041
043
B1255
A/C ambient temperature sensor open circuit
040
042
B1257
A/C ambient temperature sensor short to ground
050
052
B1261
A/C solar radiation sensor circuit short to ground


U1041
SCP invalid or missing data for function read vehicle speed


U1073
SCP invalid or missing data for engine coolant


U1222
SCP invalid or missing data for interior lamps

Note: While the above test is useful for diagnosis of suspected eatc related problems, many of the system outputs do not provide any feedback to the control head. Which means there could be numerous problems with your eatc system and you still get a "clean bill of health" from the self diagnostics. For instance, I did not recieve any error codes during the self test when I had the vacuum control block tubes & electrical connector unplugged, the air conditioner compressor request line not connected to anything, and the blend door actuator laying loose on a table without being attached to the plenum. If the eatc system were actually installed inside a vehicle like that, air would always flow from the defroster vents regardless of how the vehicle operator set the controls and temperature regulation would be nonexistent since the blend door could randomly flop around inside the plenum without any restrictions and the a/c compressor would never engage. Additionally, keep in mind that when set to the overide settings of either 60 or 90 degrees, the eatc head ignores temperature and solar radiation data and commands the blend door to either full warm or full cold position. So if you can't get heat in the 90 degree setting and cooled air in the 60 degree setting, your problem is NOT caused by the interior temperature, exterior temperature or sunload sensors.

[03blackmerc]

burp system through small acess port on the metal coolant tube on top. make sure front end is up also should put in a new t-stat real easy on the MM. well not in -5 temps lol. let it go through a few hot to cool cycles before burping.

[cougar9150]

^^^Nice :up:^^^. Great info racerx, forgot about this one.

MMinMN if you need some of the o-rings for the EATC let me know I have a big bag of them and can send you some. Doesn't look like that is the problem but if you need them I have them. I'll just drop them into an envelope and send it snail mail.

[jdando]

Ouch, no heat = really bad :snowman:

[james1986fox]

Mine was starting to blow lupe warm and the cap on my crossover tube won't come out so I just filled the over flow reservoir almost to the top drove the car and checked it the next day and filled it to the top again after doing that another time my heat has been working great.

[johnjamis]

Same thing happened to me last year. Burp it first because this is real easy to eliminate as the problem. Burp the crossover fitting by opening it and topping off with antifreeze mix. It uses a 1/4" drive, but if it is too tight you can get vice grips on the edge to help remove it. Put a little petroleum jelly or grease on the threads to help with the next removal. Don't tighten too much, as this is an o-ring seal fitting.

[MMinMN]

So I went to check it out last night. Let it warm up. No codes in EACT. Still switches from floor to vent to defrost just fine BUT when in defrost maybe 20% of the airflow is still directed to the floor. I am guesing the O-rings are beginning to leak in the EACT. Also Hot air was blowing again. Not sure what happened but it seems to have been a one time thing and fixed itself……..at least so far. Coolant was fine too. If it happens again I will be sure to update this thread.

[03blackmerc]

o its gonna happen again on an even colder day : )