Diagnostic Aids

At temperatures of about -20°F and less, A/C pressure can drop below .3 volt (7.5 psi) threshold. If this happens, Code P1530 will set and disable A/C system. Clear Code P1530 and check A/C pressure in a heated garage. If A/C pressure is between .3 volt (7.5 psi) and 4.9 volts (454 psi), A/C pressure transducer is properly functioning.

Code P1530 sets when signal voltage falls outside normal possible range of sensor. If signal voltage is greater than .1 volt, but less than .3 volt, there could be a low refrigerant pressure problem with A/C system.

Fig 1: Code P1530 Schematic (3.4L) A/C Pressure Sensor

Fig 2: Code P1530 Diagnostic Flow Chart (3.4L) A/C Pressure Sensor