P0533

Wiring Diagram:

A/C Refrigerant Pressure Sensor Circuit High Voltage:

P0533 - AIC REFRIGERANT PRESSURE SENSOR CIRCUIT HIGH VOLTAGE
The air conditioning (A/C) pressure sensor is a transducer that varies resistance according to changes in A/C high side refrigerant pressure. The ECM measures the signal voltage from the A/C pressure sensor, which is a reduced value of the ECM 5 volt reference. The voltage range of the sensor is around 0.2 - 4.9 volts (0-453 psi) gauge pressure. The sensor input is primarily used by the ECM to determine cooling fan speed under A/C operation. The sensor is also used to determine acceptable low/high refrigerant levels for safe A/C operation as well as for A/C idle speed control. DTC P0533 will set if the A/C pressure sensor signal voltage at the ECM is above the calibrated voltage value.

DTC PARAMETERS
DTC P0533 will set if A/C pressure sensor signal voltage is greater than 4.88 volts when:
^ Condition exists for longer than 0.5 seconds
^ Engine speed is greater than 40 rpm

DTC P0533 diagnostic runs continuously with engine running or cranking.

P0533 is a type D DTC

DIAGNOSTIC AIDS
To locate an intermittent problem, use Scan tool to monitor AC PRESSURE SENSOR voltage with ignition On, engine On Wiggling wires while monitoring AC PRESSURE SENSOR voltage may locate the area where an open or short to voltage in the wiring may exist.

The A/C pressure sensor may contain an intermittent open. which nay set this DTC. Run engine and operate A/C while using Scan tool to monitor AC PRESSURE SENSOR.

Circuit 416 (CMP/EGR/MAE/MAP sensor), circuit 2709 (AC pressure/fuel tank pressure sensor) and circuit 1164 (APP sensor 1) share the same 5 volt reference supply (5 volt Ref-A).

IMPORTANT: The Scan tool displays A/C HIGH SIDE PRESSURE in absolute pressure like that of a MAP sensor. To convert to gauge pressure subtract 101 kPa or 14.7 psi.

IMPORTANT: Inaccurate readings will occur if resistance measurements are taken on an A/C pressure sensor. The A/C pressure sensor contains an internal amplifier circuit that requires applied voltage to function properly.