In vehicles from the series listed above, it is possible that the air-conditioning system suddenly stops working.
A defective coolant thermostat may be the possible cause for this failure. It is controlled electronically/has an electric heating resistor.
If the error codes P0171 and P0597 (thermostat heating, electric circuit interruption) are stored in the error memory of the electronic control unit, the air-conditioning system is "deactivated" as a precaution.
Proceed as follows to rectify the problem:
Important safety note
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