it could be warning you that the temperature is -12 degrees and not at a safe level.This can be for all sorts of reasons and is difficult to diagnose without testing various bits.only thing you can do is manually defrost it for 24hrs and restart it and see if it works.Be aware if you do this and it has a system issue(lack of gas)it will kill it until you repair or replace it
ck
November 2009
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