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Discussion Starter #1
While driving down I-95 on a 90 degree temp day, my A/C stopped putting out cold air. I hit the Max Cool button and could hear the fan running in high speed, but little to no air coming out of the vents. It seemed like something was causing the the dampers to close off.

I turned off the A/C for 1/2 hour, rolled down the windows, then turned it back on. It worked fine after that. Took it into the dealer to check it out, and they told me it was a Coding issue causing the A/C to freeze up. They recoded it and said that should resolved the issue.

Does that sound right?
 

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You might want to ask the dealer for specifics on the coding issue.

When it froze up was the AC system set to auto with the fan speed set to the highest?
 

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Have you instigated coding via OBD or just through dashboard controls? Latter should not cause a conflict.

Your car is relatively new...there is a drain underneath that can get blocked...it is clear if it drips water when the chiller is on. The drain and the evaporator can get blocked with outside debris contamination or mold. Airline can unblock these IE drain and fins.

Not an expert.

:dunno:
 

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Discussion Starter #4
You might want to ask the dealer for specifics on the coding issue.

When it froze up was the AC system set to auto with the fan speed set to the highest?
The AC was on auto and I always keep the fan speed at the 2nd notch -- two up from off.

The service manager said there was a bulletin on my issue, but when I searched on line, I could find nothing???
 

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I suspect the coils froze up because of the low fan setting. It wasn't moving enough air across the coils to keep the surface above freezing so water turned to ice.
 

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Bet its low pressure in your refrigerant. They should just be able to recharge it and you'll be good assuming there isnt a leak.

If you remember back to thermodynamics isobars are horizontal lines on a TS diagram in the liquid vapor phase region. In laymens terms, the lower the pressure, the lower the isobar will be on the temperature axis. If the temperature is below the freezing point of water, your evaporator coil will turn i to a block of ice over time.
 
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