Result:

p0645

Chrysler
Type:
    Powertrain - Computer and Auxiliary Outputs - ISO/SAE Controlled
Description:
    A/C Clutch Relay Circuit Conditions
Cause:
    Key on or engine running, system voltage over 10v, A/C Clutch relay commanded on, then the PCM detected an open or short condition in the A/C Clutch relay circuit

Generic
Type:
    Powertrain - Computer and Auxiliary Outputs - ISO/SAE Controlled
Description:
    A/C Clutch Relay Control Circuit

GM
Type:
    Powertrain - Computer and Auxiliary Outputs - ISO/SAE Controlled
Description:
    Air Conditioning Clutch Relay Control Circuit Conditions
Cause:
    Engine speed over 400 rpm, system voltage from 6-18v, then the PCM detected that the Actual and Commanded state of the A/C control circuit did not match, condition met for 5 seconds

Look for code