GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2004 🢒 Colorado Pickup - 2WD 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 DTC P0532 or P0533

Circuit Description
    • P0532 Air conditioning (A/C) refrigerant pressure sensor circuit low voltage.
    • P0533 Air conditioning (A/C) refrigerant pressure sensor circuit high voltage.

The powertrain control module (PCM) monitors the high side refrigerant pressure through an 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. The PCM sends the A/C pressure data to the dash integration module (DIM) over the Class 2 serial data circuit. The DIM will command the inline A/C orifice solenoid to increase or decrease the high side pressure. This keeps the high side pressure in a normal operating range. This will prevent the A/C compressor clutch from disengaging under normal operating conditions. The DIM will not request A/C compressor clutch engagement if the A/C pressure is too high.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC
    • A/C pressure of less than 0.1 volts or more than 4.92 volts
    • The condition must be present for more than 5 seconds

Action Taken When the DTC Sets
    • The PCM will not illuminate the malfunction indicator lamp (MIL)
    • The PCM will store the conditions present when the DTC set as Fail Records data only.

Conditions for Clearing the DTC
    • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using the scan tool Clear DTC Information function.

Diagnostic Aids

Test the following conditions:

    • Visually inspect the sensor for contamination or damage.
    • Inspect for the following that may affect the sensors accuracy:
       - A malfunction within the refrigerant system causing low pressure
       - Visually inspect the A/C components and lines for damage.
    • Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Diagnostic Aids

For an intermittent, refer to in Wiring Systems.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests the ability of the A/C refrigerant pressure sensor to create a voltage signal for the PCM to monitor the A/C refrigerant pressure. Measure the voltage at the A/C refrigerant pressure sensor, if the voltage is measured at the connector for the sensor, misdiagnosis will occur.

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

1

Did you perform the HVAC Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Manual

2

Does the scan tool indicate that DTC P0532 or P0533 is current?

--

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the A/C refrigerant pressure sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the 5 volt reference circuit to the low reference circuit of the A/C refrigerant pressure sensor.

Does the voltage measure near the specified value?

5 V

Go to Step 5

Go to Step 4

4

Measure the voltage from the 5 volt reference circuit of the A/C refrigerant pressure sensor to a good ground.

Does the voltage measure near the specified value?

5 V

Go to Step 7

Go to Step 6

5

  1. With the A/C refrigerant pressure sensor disconnected, connect a jumper wire between the A/C refrigerant pressure sensor and the electrical connector of the A/C refrigerant pressure sensor for the following circuits:
    2. • The 5-volt reference circuit
    • The low reference circuit
  2. Measure the voltage at the A/C refrigerant pressure sensor terminal for the A/C refrigerant pressure sensor signal.

Does the voltage measure less than the specified value?

1.5 V

Go to Step 8

Go to Step 9

6

Test the 5-volt reference circuit of the A/C refrigerant pressure sensor for a short to ground, a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 10

7

Test the low reference circuit of the A/C refrigerant pressure sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 10

8

Test the signal circuit of the A/C refrigerant pressure sensor for a short to ground, a short to voltage, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 10

9

Inspect for poor connections at the harness connector of the A/C refrigerant pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 11

10

Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 12

11

Replace the A/C refrigerant pressure sensor. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement in Heating Ventilation and Air Conditioning.

Did you complete the replacement?

--

Go to Step 13

--

12

Important: Program the PCM.

Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls-2.8L (LK5) or DTC P0326 in Engine Controls-3.5L (L52)

Did you complete the replacement?

--

Go to Step 13

--

13
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK