Symptom 1: There are traces of coolant leaking under the vehicle, or there is significant pressure released along with coolant loss when opening the low temperature cooling system reservoir (engine cold). The following fault code may also be stored in the DME: 20A201 - Charge air cooling system: Coolant pump protective function activated due to dry running Symptom 2*: The air conditioning may have low cooling output with the following fault stored in the IHKA: 80120A - Compressor: Shut down due to overpressure in refrigerant system. Symptom 2 is an additional symptom related to Symptom 1. Diagnose the IHKA fault with ISTA test plans if it is the only fault stored (if no DME faults are stored related to coolant loss, this bulletin repair does not apply).