DTC U1021: SCP Invalid or Missing Data for Air Conditioning Clutch

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U1021 - SCP INVALID OR MISSING DATA FOR AIR CONDITIONING CLUTCH

Description:
Possible Causes:	Network DTC(s) occur during module to module communication failures. Two types of network faults can be categorized: Invalid data network faults - data is transferred within the normal inter-module message, but contains known invalid data. The transmitting module logs a DTC related to the invalid data fault. Missing message network faults - missing message faults are logged by module upon failure to receive a message from another module within a defined retry period.
Diagnostic Aids:	Carry out the on-board diagnostics for the associated network module. For additional information concerning the description and operation of the vehicle communication network, Refer to MODULE COMMUNICATIONS NETWORK .
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All	Refer to CLIMATE CONTROL SYSTEM .