P0530

Electrical Diagram:

CIRCUIT DESCRIPTION

The A/C system uses an A/C refrigerant pressure sensor mounted in the high side of the A/C system to monitor A/C refrigerant pressure. The PCM utilizes this information in order to turn ON the engine coolant fans when the A/C refrigerant pressure is high.

The A/C refrigerant pressure sensor operates much like other 3-wire sensors. The PCM supplies a 5.0 volt reference to the sensor. The sensor supplies a signal circuit to the PCM. As the A/C pressure increases or decreases, the resistance of the sensor changes and varies the amount of signal returning to the PCM.

The PCM monitors the A/C refrigerant pressure sensor signal circuit and can determine when the A/C pressure is too high or too low. When the pressures are out of range (high or low) for a predetermined time, the PCM disables the A/C compressor clutch and set a DTC P0530. When a DTC P0530 sets, the PCM disables the A/C compressor clutch so compressor damage does not occur.

CONDITIONS FOR SETTING THE DTC

^ The PCM detects an A/C request.

^ A/C refrigerant pressure sensor indicates A/C refrigerant pressure is below -8.0 psi for 5.0 seconds.

^ A/C refrigerant pressure sensor indicates A/C refrigerant pressure is above 448 psi for 5.0 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM stores the DTC information into memory when the diagnostic runs and fails.

^ The Malfunction Indicator Lamp (MIL) will not illuminate.

^ The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.


CONDITIONS FOR CLEARING THE MIL/DTC

^ A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.

^ A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.

^ The PCM battery voltage is interrupted.

^ Use a scan tool in order to clear the MIL/DTC.


DIAGNOSTIC AIDS

If the test did not fail this ignition cycle, move the related electrical harnesses and the connectors while monitoring a scan tool.

For an intermittent, refer to Symptoms. Testing and Inspection


TEST DESCRIPTION

The numbers below refer to the step numbers on the diagnostic table.

3. The normal A/C voltage is between 1.0 and 1.8 volts. If the A/C voltage is within the range, review the freeze frame data in order to determine when the DTC P0530 set.

5. If the A/C pressure/voltage stays high after disconnecting the A/C refrigerant pressure sensor electrical connector, this indicates the signal circuit is shorted to a voltage.

7. This step checks for a good ground circuit.

8. This step checks the integrity of the A/C refrigerant pressure sensor signal circuit.

11. If you have thoroughly checked the 5.0 volt reference circuit (for opens, shorts to ground, PCM connections etc.) and checks OK, then replace the PCM.

IMPORTANT: Inspect the PCM engine grounds for being secure and clean.

12. If you have thoroughly checked the ground circuit for opens and the PCM connections are OK, then replace the PCM.