2002 A/C intermittently not working

The 2002 has a hydraulic run fan. It shares the same pump and fluid as the power steering. If the radio. fan is not turning fast enough because of less oil flow to cool the A/C condenser the A/C pressure will go up so high as to shut off the A/C compressor.
So at slow MPH speed, the A/C will shut off because of low cooling airflow thru the condenser. At constant high MPH speed, the A/C would perform well because of better airflow.

I have 2003 with an electric fan. I do not know what the fan speed on your 2002 should be but I am sure it is in the Ford repair manual of how to test the fan speed and that test should be done if the A/C is shut off due to high head pressure.
 
The 2002 has a hydraulic run fan. It shares the same pump and fluid as the power steering. If the radio. fan is not turning fast enough because of less oil flow to cool the A/C condenser the A/C pressure will go up so high as to shut off the A/C compressor.
So at slow MPH speed, the A/C will shut off because of low cooling airflow thru the condenser. At constant high MPH speed, the A/C would perform well because of better airflow.

I have 2003 with an electric fan. I do not know what the fan speed on your 2002 should be but I am sure it is in the Ford repair manual of how to test the fan speed and that test should be done if the A/C is shut off due to high head pressure.
The fan has its own entire system. It doesn’t share anything with the power steering and it is functioning properly, I have not tested it to check if it is working to spec, but my issue is not speed dependent and when the fan ramps up it is plenty loud and blows plenty of air, so I’m certain that isn’t the issue. Like I said in my original post, it has a mind of its own.

I tested it about a dozen times yesterday, there was no correlation to it working and anything else. One of the times it worked in traffic, but another time it wouldn’t, one time it would work at speed, but another time it wouldn’t. I have to bring it to the shop when it isn’t cycling correctly for them to be able to diagnose it, that is the only way anyone is going to figure out what is going on here.
 
There is a self-test that can be done to determine if the HVAC computer is functioning properly. see below.

Front Panel DATC Module Self-Test (On-Demand Diagnostic Trouble Codes — DTCs)

On-demand DTCs are those that are reported by an ECU when a failure is detected while executing a diagnostic test. For the DATC module this means that all faults (hard) that occur while the module is conducting a self-test shall be reported as an on-demand DTC.
• The DATC module self-test will not detect concerns associated with data link messages such as engine coolant temperature or vehicle speed signals. The diagnostic tool must be used to retrieve these concerns.
• The vehicle interior temperature should be between 0-32°C (32-90°F) when carrying out the self-test. If the temperatures are not within the specified ranges, false temperature sensor DTCs may be displayed.

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 DEFROST buttons simultaneously and then pressing the AUTO button within 2 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 4-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.

Always exit the self-test before powering the system down (system turned OFF).

Front Panel DATC Module Display — Retrieve Continuous Diagnostic Trouble Codes (DTCs)
Continuous DTCs are fault codes recorded by the DATC module which have occurred during normal operation. For the DATC module this means that all faults (intermittent or hard) that occur while the module is in an operational state shall be reported as a continuous DTC.
• To retrieve continuous DTCs, press the OFF and DEFROST buttons simultaneously, followed by pressing the RECIRC button within 2 seconds.
• The DATC module will report all continuous DTCs to the vacuum fluorescent (VF) display.
• The DATC module will not carry out a self-test; it will only display continuous faults codes which are stored in memory.
• All VF display segments will light if no faults are detected.
• Individual continuous DTCs will be reported with the °C symbol lit.
• DTCs shall be reported as a 4-digit DTC (less the alpha character).
• Pressing the front DEFROST button will exit the retrieve continuous DTCs mode and clear all continuous DTCs from DATC module memory.
• Pressing any other button (other than DEFROST) will exit the retrieve continuous DTCs mode and maintain all continuous DTCs in DATC module memory.
• Upon exit from the retrieve continuous DTCs mode 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.
 
There is a self-test that can be done to determine if the HVAC computer is functioning properly. see below.

Front Panel DATC Module Self-Test (On-Demand Diagnostic Trouble Codes — DTCs)

On-demand DTCs are those that are reported by an ECU when a failure is detected while executing a diagnostic test. For the DATC module this means that all faults (hard) that occur while the module is conducting a self-test shall be reported as an on-demand DTC.
• The DATC module self-test will not detect concerns associated with data link messages such as engine coolant temperature or vehicle speed signals. The diagnostic tool must be used to retrieve these concerns.
• The vehicle interior temperature should be between 0-32°C (32-90°F) when carrying out the self-test. If the temperatures are not within the specified ranges, false temperature sensor DTCs may be displayed.

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 DEFROST buttons simultaneously and then pressing the AUTO button within 2 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 4-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.

Always exit the self-test before powering the system down (system turned OFF).

Front Panel DATC Module Display — Retrieve Continuous Diagnostic Trouble Codes (DTCs)
Continuous DTCs are fault codes recorded by the DATC module which have occurred during normal operation. For the DATC module this means that all faults (intermittent or hard) that occur while the module is in an operational state shall be reported as a continuous DTC.
• To retrieve continuous DTCs, press the OFF and DEFROST buttons simultaneously, followed by pressing the RECIRC button within 2 seconds.
• The DATC module will report all continuous DTCs to the vacuum fluorescent (VF) display.
• The DATC module will not carry out a self-test; it will only display continuous faults codes which are stored in memory.
• All VF display segments will light if no faults are detected.
• Individual continuous DTCs will be reported with the °C symbol lit.
• DTCs shall be reported as a 4-digit DTC (less the alpha character).
• Pressing the front DEFROST button will exit the retrieve continuous DTCs mode and clear all continuous DTCs from DATC module memory.
• Pressing any other button (other than DEFROST) will exit the retrieve continuous DTCs mode and maintain all continuous DTCs in DATC module memory.
• Upon exit from the retrieve continuous DTCs mode 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.

So I could not initiate it using those button combinations so I found a manual for a different Ford that said to press off + floor button then auto, and that did a self test of some sort. It is flashing 1947 - I don’t have the manual for our car to know what that is but another person got the same code from a 2002 Tbird that was “B1947” which was “Evap discharge temp sensor shorted to ground” - can you let me know what the manual says it should be for the self diagnostic test to confirm if that is the same code? He didn’t mention how he got his code, so I don’t know if he did it through the diagnostic tool or the self-diagnostic method.
 
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I can’t edit my last post anymore. Wanted to add that the reason my key combination is different is because the control module is different for 2002 and has the wiper heater button. From looking at the procedure for the 2002 Lincoln LS, which has the same module, the button combination is floor and off then press auto within 2 seconds.
 
I can’t edit my last post anymore. Wanted to add that the reason my key combination is different is because the control module is different for 2002 and has the wiper heater button. From looking at the procedure for the 2002 Lincoln LS, which has the same module, the button combination is floor and off then press auto within 2 seconds.
So I could not initiate it using those button combinations so I found a manual for a different Ford that said to press off + floor button then auto, and that did a self test of some sort. It is flashing 1947 - I don’t have the manual for our car to know what that is but another person got the same code from a 2002 Tbird that was “B1947” which was “Evap discharge temp sensor shorted to ground” - can you let me know what the manual says it should be for the self diagnostic test to confirm if that is the same code? He didn’t mention how he got his code, so I don’t know if he did it through the diagnostic tool or the self-diagnostic method.
The evaporator discharge temperature sensor functions to prevent the evaporator from freezing . It directs the temperature control module (the one giving you the codes) to cycle the compressor on and off to regulate the pressure in the evaporator. It can also be used to control an electronic TXV .It is a round about way of regulating evaporator superheat. If it's bad , as yours indicates , all bets are off. I should have told you to check for codes first in the control module . I think you have found your problem. Not an expensive part from what i understand , but could be in a lousy location under the dash. I will look for you and post what i find.
 
So I could not initiate it using those button combinations so I found a manual for a different Ford that said to press off + floor button then auto, and that did a self test of some sort. It is flashing 1947 - I don’t have the manual for our car to know what that is but another person got the same code from a 2002 Tbird that was “B1947” which was “Evap discharge temp sensor shorted to ground” - can you let me know what the manual says it should be for the self diagnostic test to confirm if that is the same code? He didn’t mention how he got his code, so I don’t know if he did it through the diagnostic tool or the self-diagnostic method.
Here is some data directly from the 2002 tbird manual. Your car has a regular TXV (thermostatic expansion valve) to adjust evaporator refrigerant flow. It uses the evaporator discharge temperature sensor as a means to cycle the compressor and prevent evaporator freezing . It is part number 19C734. It is located in the center dash discharge . I seem to remember you saying that you put a thermometer their. Its right where it could be poked by a dial type thermometer. Look at the location guide i copied from the manual. It is probably not too hard to replace. Its number 1 on the diagram. https://ford.oempartsonline.com/oem...8PokkdeUxxiyH4QMzLPNKADNWNyp_V5QaAt7TEALw_wcB

TB PART LOCATION.JPGTB PART NUMBER.JPGT BIRD AC SEQ OF OP.jpg
 
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2002 Chilton repair manual ;

Diagnostic Trouble Code Index

Powertrain Control Module (PCM) Diagnostic Trouble Code (DTC) Index


DTCDescriptionAction
P1460WOT A/C cutout internal driver malfunctionREFER to Diagnostics.
P1461A/C pressure sensor circuit high inputREFER to Diagnostics.
P1462A/C pressure sensor circuit low inputREFER to Diagnostics.
P1463A/C pressure sensor insufficient pressure variationREFER to Diagnostics.
P1469Low A/C cycling periodREFER to theDiagnostics manual.
P1474Low speed fan internal driver failureREFER to theDiagnostics manual.
P1479High speed fan internal driver failureREFER to theDiagnostics manual.
P1464A/C demand out of self-test rangeREFER to theDiagnostics manual.
Dual Electronic Automatic Temperature Control (DATC) Module Diagnostic Trouble Code (DTC) Index


DTCRun-Time (Intermittent) Faults or Self-Test (Hard) FaultsDescriptionAction to Take
B12421242Air flow recirculation door driver circuit failureGo To Pinpoint Test C.
B12511251Air temperature internal sensor circuit openGo To Pinpoint Test D.
B12531253Air temperature internal sensor circuit short to groundGo To Pinpoint Test D.
B12551255Air temperature external sensor circuit openGo To Pinpoint Test F.
B12571257Air temperature external sensor circuit short to groundGo To Pinpoint Test F.
B12591259Solar radiation sensor circuit openGo To Pinpoint Test G.
B12611261Solar radiation sensor circuit short to groundGo To Pinpoint Test G.
B12621262Servo motor defrost circuit failureGo To Pinpoint Test C.
B12631263Servo motor vent circuit failureGo To Pinpoint Test C.
B12641264Servo motor floor circuit failureGo To Pinpoint Test C.
B12651265Servo motor cold air bypass circuit failureINSPECT the vehicle for the presence of a cold air bypass door actuator. If a cold air bypass door actuator is present, Go To Pinpoint Test C. If a cold air bypass door actuator is not present, ignore DTC B1265.
B13421342ECU is defectiveINSTALL a new DATC module.
B16761676Battery voltage out of rangeREFER to Charging System — General Information.
B19461946Climate control A/C post evaporator sensor circuit failureGo To Pinpoint Test E.
B19471947Climate control A/C post evaporator sensor circuit short to groundGo To Pinpoint Test E.
B19661966A/C post heater sensor driver side circuit failureGo To Pinpoint Test E.
B19671967A/C post heater sensor driver side circuit short to groundGo To Pinpoint Test E.
B24282428A/C post heater sensor passenger side circuit failureGo To Pinpoint Test E.
B24292429A/C post heater sensor passenger side circuit short to groundGo To Pinpoint Test E.
B27972797Driver coolant control valve open circuitGo To Pinpoint Test J.
B27982798Driver coolant control valve circuit short to groundGo To Pinpoint Test H.
B27992799Passenger coolant control valve open circuitGo To Pinpoint Test J.
B28002800Passenger coolant control valve circuit short to ground
 
2002 Chilton repair manual ;

Diagnostic Trouble Code Index

Powertrain Control Module (PCM) Diagnostic Trouble Code (DTC) Index


DTCDescriptionAction
P1460WOT A/C cutout internal driver malfunctionREFER to Diagnostics.
P1461A/C pressure sensor circuit high inputREFER to Diagnostics.
P1462A/C pressure sensor circuit low inputREFER to Diagnostics.
P1463A/C pressure sensor insufficient pressure variationREFER to Diagnostics.
P1469Low A/C cycling periodREFER to theDiagnostics manual.
P1474Low speed fan internal driver failureREFER to theDiagnostics manual.
P1479High speed fan internal driver failureREFER to theDiagnostics manual.
P1464A/C demand out of self-test rangeREFER to theDiagnostics manual.
Dual Electronic Automatic Temperature Control (DATC) Module Diagnostic Trouble Code (DTC) Index


DTCRun-Time (Intermittent) Faults or Self-Test (Hard) FaultsDescriptionAction to Take
B12421242Air flow recirculation door driver circuit failureGo To Pinpoint Test C.
B12511251Air temperature internal sensor circuit openGo To Pinpoint Test D.
B12531253Air temperature internal sensor circuit short to groundGo To Pinpoint Test D.
B12551255Air temperature external sensor circuit openGo To Pinpoint Test F.
B12571257Air temperature external sensor circuit short to groundGo To Pinpoint Test F.
B12591259Solar radiation sensor circuit openGo To Pinpoint Test G.
B12611261Solar radiation sensor circuit short to groundGo To Pinpoint Test G.
B12621262Servo motor defrost circuit failureGo To Pinpoint Test C.
B12631263Servo motor vent circuit failureGo To Pinpoint Test C.
B12641264Servo motor floor circuit failureGo To Pinpoint Test C.
B12651265Servo motor cold air bypass circuit failureINSPECT the vehicle for the presence of a cold air bypass door actuator. If a cold air bypass door actuator is present, Go To Pinpoint Test C. If a cold air bypass door actuator is not present, ignore DTC B1265.
B13421342ECU is defectiveINSTALL a new DATC module.
B16761676Battery voltage out of rangeREFER to Charging System — General Information.
B19461946Climate control A/C post evaporator sensor circuit failureGo To Pinpoint Test E.
B19471947Climate control A/C post evaporator sensor circuit short to groundGo To Pinpoint Test E.
B19661966A/C post heater sensor driver side circuit failureGo To Pinpoint Test E.
B19671967A/C post heater sensor driver side circuit short to groundGo To Pinpoint Test E.
B24282428A/C post heater sensor passenger side circuit failureGo To Pinpoint Test E.
B24292429A/C post heater sensor passenger side circuit short to groundGo To Pinpoint Test E.
B27972797Driver coolant control valve open circuitGo To Pinpoint Test J.
B27982798Driver coolant control valve circuit short to groundGo To Pinpoint Test H.
B27992799Passenger coolant control valve open circuitGo To Pinpoint Test J.
B28002800Passenger coolant control valve circuit short to ground
That's good info T. The 1947 code he is getting is for a high failure part called the Evaporator discharge temperature sensor. It is most likely shorted out. It is located right behind the center air outlet where he is putting his thermometer. Its a $20 part but may be a bitch to install. Read what i posted for him. These new cars have entirely too much bullcrap electrical sensors that simply are not needed for a decent working a/c and usually they are behind the dash in a hell hole location.Runs the cost up to service them far too much. Randy
 
Thank you for sharing that information, I will be buying a service manual as well.

I have to remove the stereo to attempt to fix the CD changer, I don’t care if I can’t get it working again, I need my Grandpa’s old CD’s out because they have sentimental value to my others cousins and my Grandma. While doing that, I will see how easy it is to access the part. If I can get to it, I will replace it at the same time, if it requires the whole dash to be pulled, I will wait until the winter.
 
I am a licensed HVACR technician, I only work on ac systems I own, mainly rental properties. I also work on 80 ton systems at my 500,000 sq ft office warehouse. I do work on vehicle ac systems only when I am helping someone out, which lately seems to be more often that I care to. I even have my 609 certification which allows me to work on any motor vehicle air condition system.

I always work back wards it is faster, and easier. First I try operating the ac system normally, and see what the system is doing, while my gauges are connected. If system is not operational, I disconnect the ac clutch wire, and manually apply voltage to the clutch, this gets the system running, and allows me to look at pressures, and see if cooling is adequate.

If system is cooling, then you work backwards, looking at relays, electronic controls, sensors, sooner rather than later you find the problem.
 
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I am a licensed HVACR technician, I only work on ac systems I own, mainly rental properties. I also work on 80 ton systems at my
500,000 sq ft office warehouse. I do work on vehicle ac systems only when I am helping someone out, which lately seems to be
more often that I care to. I even have my 609 certification which allows me to work on any motor vehicle air condition system.

I always work back wards it is faster, and easier. First I try operating the ac system normally, and see what the system is doing,
while my gauges are connected. If system is not operational, I disconnect the ac clutch wire, and manually apply voltage to the
clutch, this gets the system running, and allows me to look at pressures, and see if cooling is adequate.

If system is cooling, then you work backwards, looking at relays, electronic controls, sensors, sooner rather than later you find
the problem.
I am a retired HVAC/ELECTRONICS instructor with many years of field experience I have my Universal Refrigerant license and my MVAC one as well. I like your approach. These cars are a PIA they have far too many sensors and other bull that fails and are usually in a crummy location to replace. I generally use troubleshooting by division , what works what does not as you do. Trouble is , as a i am sure you know that only a little knowledge of an a/c system can get you in trouble and lead you in the wrong direction. Stealerships will immediately replace "common fail" items and if that works they will charge you "full book time" on labor. I have seen this done all my life.
 
I finally had time this past weekend to remove the evaporator discharge air temp sensor, thankfully I found another post (link below) that showed the location of the sensor and it was in an accessible area. The car bit me a couple times and the sensor gave me a hard time, but after about 45mins of pulling and prying, it came out; mine seemed to be more stubborn than others. I then tested the resistance and it was reading around 300 ohms, it should be in the 25-33k range, from what I could find online. Ordered the part and installed it today. Self diagnostic showed no errors and my AC is working great!! So happy to finally have this fixed! Thanks again for everyone’s help!

Part number: YH-1504 - https://www.ebay.com/sch/i.html?LH_...teid=0&campid=5338236430&toolid=20008&mkevt=1

Location:
https://forums.fordthunderbirdforum...harge-air-temperature-sensor-2002-tbird.8933/

P.S. To any 2002 owners who want to run the self diagnostic on the DATC, follow these direction: with the key on “run” and DATC off, press the “floor mode” and “off” buttons together, then “Auto” - this can be run with the engine running, or while driving as well.
 
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Hello all. My wife and I inherited a 2002 Thunderbird that is a bit of disarray. I'm not getting any hot air. I ran the OFF/FLOOR/AUTO test and got a 1242 error code. I've already read and replaced the DCCM and bled the cooling system. The lines going into and out of the heater core are hot. The three on the firewall. I see in the post earlier it referenced Pinpoint Test C. I clicked that link and get the Las Vegas library. Any other ideas on the topic. I've read almost every post on the topic and they all pointed at the DCCM module, and I replaced, but the hose lines into/out of the core were hot before. Is it the door actuator?
 
Hello all. My wife and I inherited a 2002 Thunderbird that is a bit of disarray. I'm not getting any hot air. I ran the OFF/FLOOR/AUTO test and got a 1242 error code. I've already read and replaced the DCCM and bled the cooling system. The lines going into and out of the heater core are hot. The three on the firewall. I see in the post earlier it referenced Pinpoint Test C. I clicked that link and get the Las Vegas library. Any other ideas on the topic. I've read almost every post on the topic and they all pointed at the DCCM module, and I replaced, but the hose lines into/out of the core were hot before. Is it the door actuator?
Hello, you should start a new topic as your issue doesn't relate to the issue I was having in this thread and a fresh thread will get more bites from people.

To see the testing required you need a copy of the service manual. I would help by posting the test needed, but it is 24 steps and there are other sections you have to refer to for finding the connection points, etc.
 
Hello, you should start a new topic as your issue doesn't relate to the issue I was having in this thread and a fresh thread will get more bites from people.

To see the testing required you need a copy of the service manual. I would help by posting the test needed, but it is 24 steps and there are other sections you have to refer to for finding the connection points, etc.
Thanks for the heads up. I did buy the service manual electronic version, but I don't think it is complete.
 
After dealing with all the things that go wrong with these 2002 Thunderbirds, I solved the problems by selling it. It seams no one can fix the A/C 's on these cars. I replaced everything, but it never lasted long before needing help again. When you get tired of spending money on endless repairs, let someone else in a location that doesn't require the A/C enjoy it. (Sold mine for $6500) as is.
 
Sad to see you sold your T Bird, I do not think these cars are any harder to repair than most other cars of the same years. If you search the
internet, you will see other cars have issues with the same parts. It was the best technology available at the time, and again remember nothing
lasts forever. These cars are 20 years old now, and do need some attention now and then.

Some of the repair issues are due to dealerships not knowing how to work on this era of electronics. Most of the mechanics working
when these cars were produced, are now retired. Mechanics working today, were trained with todays technology, not yesterdays
technology, so they do not know how to repair.

Sometimes we get lucky and find a mechanic that is still working, and was trained to work on cars during T Birds era. I have three
2002 T Birds, and I do all of my own repairs. I have had very few problems, and find them easy to work on, because if I were a
mechanic, I would have been a mechanic during the T Birds time.
 
After dealing with all the things that go wrong with these 2002 Thunderbirds, I solved the problems by selling it. It seams no one can fix the A/C 's on these cars. I replaced everything, but it never lasted long before needing help again. When you get tired of spending money on endless repairs, let someone else in a location that doesn't require the A/C enjoy it. (Sold mine for $6500) as is.
A 20 year old car with over 144,000 miles on it, according to your post in June, is bound to have issues. Heck, a 20 year old car's AC system with any mileage is bound for failure at some point.
 
I have the same issues as you have. Replaced the 5 port DCCV, and no help. Had a shop evacuate system, and reservice, weeks later returned to shop and was told freon was low. Added freon, and was good for another week or so. After reading forum, it seems the O rings go bad and bypass freon, so the compressor has to be replaced. Mine was replaced about 8 years ago, and I guess is due again. Read the blogs, it seems to be a common problem (one of many) with these cars.
Have the same issue how much for repairs for that
 
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