DTC P1531: Low A/C Refrigerant Charge: Notes

PCM monitors A/C request signal circuit and completes ground for A/C relay when A/C mode is selected at control head and refrigerant pressure is sufficient to close A/C pressure cycling switch. If refrigerant pressure is low and A/C request signal causes PCM to cycle compressor too often, PCM protects compressor by disabling A/C relay and storing Code P1531.

Code P1531 will set when the following condition is present.

• A/C compressor cycles on 10 or more times within 15 minutes and compressor on time for each cycle is less than 1.5 seconds.