Dual climate control blowing heat on AC (DCCV removal instructions in post #107)

[mpres2]

I charged my A/C system with freon and it fixed the problem. It was confusing because there was such a differential from the driver's side to the passenger side. I'm still not sure why the passenger side seemed so much warmer than the driver's side. Also, the temp here in Texas is currently above 100 degrees.

Thanks all for all the info posted here.
Mpres2

[proplumb]

a/c kicked off again on xway @ 70 mph. The fan speed kicks up because it's on auto and it trys to recover. Hot air out of drivers side. cooler air out of pass. side but not cold. If we stop and restart the car the a/c works again fine. I have a cheep A/C gauge that tells you if it needs a charge. with the a/c on full the guage reads ok. When the clutch for the compressor kicks on the charge goes down to the line which separates the needs charge to the ok side. When the compressor clutch kicks off, the ok part of the charge returns to normal. The clutch kicks in and it drops to the needs and ok line. The a/c dosen't go out when we just drive around town, only at higher speeds. No codes from a/c self test. Thanks

[shorod]

You probably will need to install a manifold gauge set so you can get actual pressure readings on both the high and low sides simultaneously to condemn or rule out the R-134a charge as the cause.

-Rod

[Mr.T777]

I also have a problem with DCCV! I got 2798 on Self-test. Does this mean only DCCV need to be replaced?? Anyone have instructions on how to change DCCV in '04 V6 LS? Thanks-

[ADeloge340]

I received code 24 77. Any help is greatly appreciated.

[shorod]

That's an interesting code. The description, according to the factory service manual, is "Module configuration failure." The solutions says to "reconfigure the DATC module. Assuming you have not recently replaced the DATC module and it has worked in the past, and you do not have access to a Ford WDS tool, I think I'd start by resetting the DATC (similar to the self-test).

-Rod

[joegr]

Originally Posted by shorod

That's an interesting code. The description, according to the factory service manual, is "Module configuration failure." The solutions says to "reconfigure the DATC module. Assuming you have not recently replaced the DATC module and it has worked in the past, and you do not have access to a Ford WDS tool, I think I'd start by resetting the DATC (similar to the self-test).

-Rod

Won't work. The DATC will have to be replaced or reconfigured with the Ford scan tool. It's rare, but I've seen it before.

[shorod]

ADeloge340, depending on the model year and options (heated/cooled seats) I may have a working DATC that I'd sell to you for less than what Ford would charge to reconfigure it. Send me a PM if you're interested.

Joegr, any idea what causes these to lose configuration? Does it seem to be indicative of an old/weak battery?

-Rod

[joegr]

Originally Posted by shorod

ADeloge340, depending on the model year and options (heated/cooled seats) I may have a working DATC that I'd sell to you for less than what Ford would charge to reconfigure it. Send me a PM if you're interested.

Joegr, any idea what causes these to lose configuration? Does it seem to be indicative of an old/weak battery?

-Rod

Sorry, no I don't. I suspect that it's an internal failure of the memory. ESD can cause this in general, but I don't know if it could be the cause specifically for the LS DATC. It seems unlikely that the operator could cause a discharge into the DATC electronics.

[shorod]

If it were ESD damage reconfiguring it wouldn't fix it. But RAM corruption wouldn't be all that unheard of I guess.

-Rod

[joegr]

Originally Posted by shorod

If it were ESD damage reconfiguring it wouldn't fix it. But RAM corruption wouldn't be all that unheard of I guess.

-Rod

Disclaimer: The related experiences do not apply directly to an LS DATC.

Actually I have seen microcontrollers with FLASH memory that could be restored to correct operation by reprogramming the FLASH after they stopped working correctly after an ESD hit.

I agree that this seems odd and that RAM corruption is much easier to understand.

[nuckolsk]

Originally Posted by shorod

Well, for the 2004 there is not a designation between the process for DATC with climate controlled seats versus without. Did all V8 models have climate controlled seats?

The manual claims you access the codes with the following sequence:
------------
The DATC module self-test through the front panel display:
can be initiated at any time. Normal operation of the system stops when the self-test is activated.
is entered by pressing the OFF and FLOOR buttons simultaneously and then pressing the AUTO button within two seconds . Record all DTCs displayed.
concludes by reporting all on-demand DTCs. Follow the diagnostics procedure given under ACTION in the DTC index for each DTC given.
reports individual on-demand DTCs as four-digit DTCs (less the alpha character).
will calibrate all the mode doors and check all analog inputs. The DATC module will only report on-demand (hard) faults that occurred while the DATC module was conducting its self-test.
will light all control panel display segments if no faults are detected.
will report individual on-demand DTCs without the °C symbol lit.

To exit the self-test, press the defrost button. This will clear all on-demand codes from the DATC module memory. If no button is pushed, DTCs will continue to be displayed.

Upon exit from the self-test the DATC module returns to operational status. The DATC module executes a hard (cold boot) reset which places the DATC system in the OFF mode.
------------

For what it's worth, I'm claiming success in getting the issue fixed on my wife's LS. My scan tool showed that the Evaporator Core Air Discharge temp sensor was not in range. There were no codes, but the datastream showed no changes in the reading and it appeared to be maxed out at 255 degrees F, even when the vent temp was 45 degrees F. Replaced the sensor and all has been well for 2 weeks of mixed weather.

-Rod

rod the sensor you talking about. is that one of the 3 under the dash ( same as the pic attachments to this thread ) ?

[shorod]

Originally Posted by nuckolsk

rod the sensor you talking about. is that one of the 3 under the dash ( same as the pic attachments to this thread ) ?

Yes, it was one of the sensors on the driver's side under the dash. Off the top of my head, I thought there were three sensors on the driver's side of my wife's 2002. With my scan tool monitoring the sensors I unplugged them one at a time until I found one that didn't have an effect on the readings of the scan tool and replaced that one. I then swapped that sensor with the one on the passenger side and confirmed the temp reading followed the sensor. I think it was the even the easiest one to get to on the driver's side.

-Rod

[nuckolsk]

Originally Posted by shorod

The panel button is the button that would direct air through the dash panel vents.

Since you got the display to count to 25, it sounds like you ran through the module self test rather than the self test to retrieve continous Diagnostic Trouble Codes (DTCs). The module self test will only report on-demand DTCs.

The module self test is initiated by pressing the OFF and FLOOR buttons simultaneously followed by the AUTO button. To retrieve the continuous DTCs you press the OFF and PANEL buttons followed by the AUTO button. I believe the details are listed in this thread, so I won't repeat them here.

-Rod

is that for a 2000 also? i keep doing the first test and got all ok.

[shorod]

I suspect that would work on the 2000 as well, and if you try it and it gives results that indicate everything is okay rather than some strange result, or nothing at all, then it's probably performing the self test as designed.

-Rod