HVAC System - Automatic

DTC P0530

Circuit Description

The powertrain control module (PCM) monitors the high side refrigerant pressure through a air conditioning (A/C) refrigerant pressure sensor. When the pressure is high the signal voltage is high. When the pressure is low the signal voltage is low. When pressure is high the PCM commands the cooling fans ON. When pressure is too high or too low the PCM will not allow the A/C compressor clutch to engage.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0530 Air Conditioning Refrigerant Pressure Sensor Circuit

Conditions for Running the DTC

The PCM detects the signal circuit is less than 5 counts (0.09 volts) or more than 250 counts (4.90 volts).

Conditions for Setting the DTC

The condition exists for 20 seconds.

Action Taken When the DTC Sets

* The PCM will not illuminate the malfunction indicator lamp (MIL).
* The PCM stores the failure records.
* The A/C compressor clutch is disabled.

Conditions for Clearing the DTC

* The DTC will become history if the PCM no longer detects a failure.
* The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
* The DTC can be cleared with a scan tool.

Test Description

Step 1 - Step 8:

Step 9 - Step 17:

The numbers below refer to the step numbers on the diagnostic table.
4. Tests for the proper operation of the circuit in the low voltage range.
5. Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
6. Tests for a short to voltage in the 5-volt reference circuit.
7. Tests for a high resistance or an open in the low reference circuit.
16. Perform the programming procedure for the PCM.