A/C Refrigerant Pressure Sensor

The A/C system is protected by the A/C refrigerant pressure sensor. The sensors' output to the PCM is variable and is dependent upon pressure inside the line. A higher pressure results in a higher voltage output. The A/C pressure is constantly monitored in order to allow the A/C compressor clutch to disengage as needed.

If line pressures climb above 2979 kPa (432 psi), the PCM will turn off the A/C compressor clutch until the pressure lowers to 1510 kPa (219 psi). If line pressures fall below 186 kPa (27 psi), the PCM will turn off the A/C compressor clutch until the pressure raises to 207 kPa (30 psi).

A 5-volt reference signal is sent out over the 5-volt reference circuit, from the PCM, to the A/C refrigerant pressure sensor. The PCM monitors the A/C pressure by sending out a separate 5-volt signal on the A/C refrigerant pressure sensor signal circuit. This circuit is how the PCM monitors HVAC pressures. Ground for the A/C refrigerant pressure sensor is provided by the low reference circuit.

"For the description of RPO code(s) shown in this article or any of the images therein, refer to the RPO code list found at the Vehicle/Application And ID." RPO Codes