TSB 14-0220 INTERMITTENT LACK OF A/C - AFTER EXTENDED DRIVING AND HOT HUMID CONDITIONS - EVAPORATOR CORE ICING

[Bill-N]

TSB 14-0220 INTERMITTENT LACK OF A/C - AFTER EXTENDED DRIVING AND HOT HUMID CONDITIONS - EVAPORATOR CORE ICING 

 

Publication Date:  December 8, 2014

 

FORD: 2013-2014 Escape
            2013-2015 C-MAX

LINCOLN: 2015 MKC

 

This article supersedes TSB 14-0218 to update the Parts List.

 

ISSUE:

Some 2013-2014 Escape vehicles built on or before 7/22/2014, 2015 MKC vehicles built on or before 7/13/2014 and 2013-2015 C-MAX and may exhibit an intermittent lack of Air Conditioning (A/C) and/or a loss of airflow from the vents. This may occur after extended operation in hot, humid conditions. This is likely due to the evaporator core icing.

 

ACTION:

Follow the Service Procedure Steps to correct the condition.

 

SERVICE PROCEDURE

1. Evacuate and Recharge the A/C System. Refer to the Workshop Manual (WSM), Section 412-00.
   1. Make sure the same amount of oil recovered is returned to the A/C system.

2. Replace the cabin air filter. Refer to WSM, Section 412-00.

3. Replace the evaporator temperature sensor. Refer to WSM, Section 412-00. 

Edited February 4, 2015 by Bill-N

[bigalpha]

One of my AC lines froze up today on the way home from work.  It's the line that goes from the compressor, up and over to the passenger side, then disappears under the coolant tank.  Is this what this particular TSB is referring to?

[plus 3 golfer]

One of my AC lines froze up today on the way home from work. It's the line that goes from the compressor, up and over to the passenger side, then disappears under the coolant tank. Is this what this particular TSB is referring to?

No, it's referring to the evaporator core inside the HVAC box under the center of the dash. Evidently there's a faulty temp sensor which is incorrectly reporting the evaporator core temperature higher than actual. So, the AC compressor continues to operate lowering the evaporator core temperature too low which then freezes the condensation on the core. Ice forms and continues to build on the core restricting air flow through the core. Edited July 11, 2015 by Plus 3 Golfer

[bigalpha]

Hmm.  Is there a way I can test this problem myself instead of having the dealer do it?  I wonder if this is covered under the extended warranty?

[scottwood2]

I wonder if this is covered under the extended warranty?

I thought it was covered because it was a TSB even out of warranty but that is not true.  Looks like it could be covered by extended warranty but not the standard warranty.  

 

http://www.explorerforum.com/forums/showthread.php?t=407478

[FordService]

Hmm.  Is there a way I can test this problem myself instead of having the dealer do it?  I wonder if this is covered under the extended warranty?

 

 

I thought it was covered because it was a TSB even out of warranty but that is not true.  Looks like it could be covered by extended warranty but not the standard warranty.  

 

http://www.explorerforum.com/forums/showthread.php?t=407478

 

Hi guys,

 

A Technical Service Bulletin (TSB) is a supplement to a vehicle's repair manual and does not suggest nor provide additional coverage. Coverage of any repair is determined by eligibility under the provisions of the New Vehicle Limited Warranty, a Customer Satisfaction Program or a Recall.

 

Your dealer will be in the best position to determine if something falls under warranty. Have you had a chance to set up an appointment?

 

Meagan

[bigalpha]

My car is 60k miles out of factory warranty, so I'm hoping that the extended warranty can cover this.  I have an appointment for Monday.

[FordService]

My car is 60k miles out of factory warranty, so I'm hoping that the extended warranty can cover this.  I have an appointment for Monday.

 

Once you get a diagnosis, please PM me your VIN, updated mileage, best daytime phone number, full name, and dealer name/location. I'll check out some options.

 

Meagan

[bigalpha]

Once you get a diagnosis, please PM me your VIN, updated mileage, best daytime phone number, full name, and dealer name/location. I'll check out some options.

 

Meagan

 

Thanks, that's much appreciated!

[FordService]

Thanks, that's much appreciated!

 

You're welcome!

 

Meagan

[bobmaxed]

Hello

           Having A/C problems on my 2014 C-Max SE.   Intermittent lack of A/C and loss of airflow  just like this TSB states.  But this is the first time this problem has come up and this is the third summer we've had the car.  It's near 50,000 miles so its out of warranty.   Trying to determine if I should take it to the local Ford dealer or search out a reputable generic repair shop.  Could it just be a blocked drain, and where is the drain on this car?

 

Thanks

[plus 3 golfer]

Hello

           Having A/C problems on my 2014 C-Max SE.   Intermittent lack of A/C and loss of airflow  just like this TSB states.  But this is the first time this problem has come up and this is the third summer we've had the car.  It's near 50,000 miles so its out of warranty.   Trying to determine if I should take it to the local Ford dealer or search out a reputable generic repair shop.  Could it just be a blocked drain, and where is the drain on this car?

 

Thanks

There's certainly a drain but I doubt that is the issue.  

 

It's probably the temperature sensor if you have no air flow as that would indicate something is blocking the air flow through the evaporator core (likely the condensate is freezing).   It's probably not too difficult to replace the temp. sensor.  When I have time I'll look at the service manual.  

 

This is another case where the ForScan smartphone app would likely help in troubleshooting as there's likely data / diagnostic trouble codes available.

[stevedebi]

Hello

           Having A/C problems on my 2014 C-Max SE.   Intermittent lack of A/C and loss of airflow  just like this TSB states.  But this is the first time this problem has come up and this is the third summer we've had the car.  It's near 50,000 miles so its out of warranty.   Trying to determine if I should take it to the local Ford dealer or search out a reputable generic repair shop.  Could it just be a blocked drain, and where is the drain on this car?

 

Thanks

I have this happen at least once or twice per summer. Here is what I do. I think the compressor is frozen, because this always fixes it.

 

Make sure Recirc is off (so you are bringing in fresh air). Turn the A/C button OFF and the fan to at least three or four. After just a minute, the outside air will defrost the compressor and you will have A/C. Works every time for me.

 

But maybe I should have them check that TSB...

[plus 3 golfer]

I have this happen at least once or twice per summer. Here is what I do. I think the compressor is frozen, because this always fixes it.

 

Make sure Recirc is off (so you are bringing in fresh air). Turn the A/C button OFF and the fan to at least three or four. After just a minute, the outside air will defrost the compressor and you will have A/C. Works every time for me.

 

But maybe I should have them check that TSB...

First, I think you mean the evaporator core ices up (not the compressor).  Second, this doesn't "fix" the issue as the evaporator temperature sensor should cut off the compressor before the evaporator core freezes.  It's likely the sensor is faulty. 

 

The evaporator temp sensor measures the air temperature of the air exiting the core.  Normally, if the evaporator discharge air temperature is below approximately 35.6 °F, the compressor is "shut" off to prevent icing of the evaporator core.  

 

I haven't looked up the price of the evaporator core sensor but I doubt it would be more than $20-$30.  Replacement is easy as it appears to be behind a small cover (maybe 4" x 4") on the right side of the driver's center console foot well panel.  See below.

Edited July 6, 2016 by Plus 3 Golfer

[plus 3 golfer]

This appears to be the evaporator temperature sensor:  A/C Evaporator Temperature Sensor MOTORCRAFT YH-1771

 

MSRP is $11.98 per Fordparts.com

 

For those out of warranty or with a high deductible on an extended warranty, I'd just buy it for $12 and put it in.   Dealer will likely charge $100 just to diagnose, $12 for part + labor assuming the dealer does nothing with respect to the refrigerant system.  I'd be careful as some shops (not only dealers) will likely also evacuate refrigerant, change dryer, and recharge for $100s more. ;)  One could end up with a $300-$500 bill for a $12 part and likely 15 minutes of ones time.

Edited July 6, 2016 by Plus 3 Golfer

[bobmaxed]

Thank you very much for the quick and thorough responses.  Looks like a no brainer.   Replace the sensor myself before going anywhere near a repair shop.

 

Bob

[plus 3 golfer]

Thank you very much for the quick and thorough responses.  Looks like a no brainer.   Replace the sensor myself before going anywhere near a repair shop.

 

Bob

I think it's worth trying for $12 and see if the issue goes away. 

 

Another possible cause of evaporator icing (that I can think of) might be low refrigerant in the system (other than control circuit / electronics).  The fact that the TSB applies to only certain vehicles might indicate a batch of bad sensors or inadequate factory charging.  I note that the TSB does not assume that there may be a leak (loss of refrigerant), bad compressor and so forth as it does not mention these as a possibility or to check.

 

I guess it's possible with a slightly lower refrigerant charge and higher humidity, that the icing process will block only part of the evaporator core starting from where the liquid enters the core and the sensor cannot accurately read the temperature of the evaporator core air.  There is not enough liquid refrigerant to "evaporate" in the evaporator coil and freeze the entire core (as might happen with a bad sensor).  So, the coil partially freezes, air flow diminishes, and warmer air flows through the part of the coil not iced such that the evaporator temperature is above the the threshold temperature to cutoff the compressor and the compressor continues to run resulting in low air flow and diminished cooling.   So to minimize Ford's cost under warranty when a customer has this "known" issue, it's likely cheaper to evacuate, recharge, change filter and temperature sensor rather than to pay the dealer time for first troubleshooting and then time to fix.

 

There are many DTC for the Climate Control System.  Below are some that may be relevant.

 

PCM DTC

P0532    A/C Refrigerant Pressure Sensor “A” Circuit Low

P0533    A/C Refrigerant Pressure Sensor “A” Circuit High

 

BCM DTC              

B1B71:21              Evaporator Temperature Sensor: Signal Amplitude < Minimum

B1B71:22              Evaporator Temperature Sensor: Signal Amplitude > Maximum

B1B71:2F              Evaporator Temperature Sensor: Signal Erratic

[stevedebi]

First, I think you mean the evaporator core ices up (not the compressor).  Second, this doesn't "fix" the issue as the evaporator temperature sensor should cut off the compressor before the evaporator core freezes.  It's likely the sensor is faulty. 

 

The evaporator temp sensor measures the air temperature of the air exiting the core.  Normally, if the evaporator discharge air temperature is below approximately 35.6 °F, the compressor is "shut" off to prevent icing of the evaporator core.  

 

I haven't looked up the price of the evaporator core sensor but I doubt it would be more than $20-$30.  Replacement is easy as it appears to be behind a small cover (maybe 4" x 4") on the right side of the driver's center console foot well panel.  See below.

I'm sure you are correct. I was just sharing what I do to get past it. Maybe I'll schedule a trip to the dealer, since I am under warranty. The problem is, they will want to see the issue before they fix it.

[notquitesane]

I had the a/c evap freeze up on me for the first time this year.  I noticed that when the climate control system was set to auto, it started acting differently. The blower motor started to stay on a fairly low speed while the inside of the car kept getting warmer.  On the way to a museum in Wetaskiwin, no air was coming out of the vents despite the blower making a lot of noise.  After we were done with the museum, everything worked like normal.  After some searching I stumbled upon this thread.

 

Last week I was leaving for a trip so I had no time to take the car in for the dealer to look at this issue but I was able to pick up the temp sensor. It was cheap, easy to replace.  All the weird issues with the climate control system set to auto are gone.  Everything works the way it did when I bought the car 1.5 years ago.  Let's hope that was the issue.

[bigqueue]

Is the AC used to cool the battery? Would I ever see this problem if I never used the AC to cool the passenger compartment?

 

Thanks...and great information!

[Bill-N]

I doubt the AC cools the HV battery.  But peek at a service manual to be sure.

[stolenmoment]

The HV battery gets air from the cabin, so, it does so rather indirectly.

[Cmaxer]

After spending $400 to have the TSB done it turned out to be a dust saturated Cabin Air Temperature Sensor located above the knee of the driver. I used canned compressed air and directed the flow into the fan blades of the sensor and witnessed a puff of dust twice come out the sensor. Funny that the malfunctioning of the cooling system from this sensor coincided with the return of the car from the autobody shop.

[Billyk24]

17 hours ago, Cmaxer said:

After spending $400 to have the TSB done it turned out to be a dust saturated Cabin Air Temperature Sensor located above the knee of the driver. I used canned compressed air and directed the flow into the fan blades of the sensor and witnessed a puff of dust twice come out the sensor. Funny that the malfunctioning of the cooling system from this sensor coincided with the return of the car from the autobody shop.

my 2017 Energi has the cabin air temperature sensor in the passenger side of the front cabin area near where the knees are. 

 

[Lacienega]

17 hours ago, Cmaxer said:

After spending $400 to have the TSB done it turned out to be a dust saturated Cabin Air Temperature Sensor located above the knee of the driver. I used canned compressed air and directed the flow into the fan blades of the sensor and witnessed a puff of dust twice come out the sensor. Funny that the malfunctioning of the cooling system from this sensor coincided with the return of the car from the autobody shop.

Is it under the cover that says airbag below the steering wheel?