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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Seville 🢒 DTC 🢒 DTC P0532 Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit Low Voltage

Object Number: 603425 Size: SF
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Circuit Description

The A/C system uses an A/C refrigerant pressure sensor mounted in the high pressure side of the A/C refrigerant system. The A/C pressure sensor responds to changes in the A/C refrigerant pressure. The PCM uses this information to turn ON the engine coolant fans when the A/C pressure is too high. The PCM also uses the information to disengage the A/C compressor when the A/C refrigerant pressure is excessively high or low. The PCM supplies the sensor with a 5 volt reference and a ground. The sensor returns a signal voltage relative to A/C refrigerant pressures. The PCM monitors the A/C pressure sensor to detect signal voltages outside of the possible range of the sensor. When the PCM detects an A/C pressure signal that is excessively low, DTC P0532 will set.

Conditions for Running the DTC
    • The engine is running.
    • A/C has been requested.

Conditions for Setting the DTC
    • The A/C pressure sensor signal is less than 0.1 volt.
    • The condition exists for 3 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 Failure Records data only.

Conditions for Clearing the MIL/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

If the condition is intermittent, refer to Intermittent Conditions .

Step

Action

Values

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Is DTC P1639 also set?

--

Go to DTC P1639 5 Volt Reference 2 Circuit

Go to Step 3

3

Observe the A/C High Side Pressure display on the scan tool.

Does the scan tool indicate an A/C High Side Pressure more than the specified value?

0.25V

Go to Step 4

Go to Step 5

4
  1. Turn ON the ignition, with the engine OFF.
  2. Review and record the scan tool Fail Records data.
  3. Operate the vehicle within the Fail Records conditions.
  4. Using the scan tool, monitor the Specific DTC Information for DTC P0532.

Does the scan tool indicate that DTC P0532 failed last test?

--

Go to Step 5

Go to Diagnostic Aids

5

  1. Turn OFF the ignition.
  2. Disconnect the A/C pressure sensor connector.
  3. Connect test lamp between battery positive voltage and the A/C pressure sensor circuit in the harness connector.
  4. Turn ON the ignition, with the engine OFF.

Is the test lamp ON?

--

Go to Step 11

Go to Step 6

6

  1. Leave the ignition ON with the engine OFF.
  2. Leave test lamp connected between battery positive voltage and the A/C pressure sensor signal circuit.
  3. Observe the A/C High Side Pressure display on the scan tool.

Does the scan tool display a voltage near the specified value?

5 volts

Go to Step 7

Go to Step 8

7

  1. Leave the ignition ON with the engine OFF.
  2. Connect DMM between the 5 Volt Reference B circuit and ground.

Does the DMM display a voltage near the specified value?

5 volts

Go to Step 9

Go to Step 10

8

  1. Test the A/C pressure sensor signal circuit for an open or poor connections at the PCM.
  2. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

9
  1. Test for an open or poor connections at the A/C pressure sensor.
  2. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 12

10
  1. Test for poor connections at the PCM.
  2. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

11
  1. Turn OFF the ignition.
  2. Disconnect the PCM connector.
  3. Test the A/C pressure sensor signal for a short to ground or the A/C pressure sensor ground. Refer to Wiring Repairs in Wiring Systems.
  4. If the condition is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 14

Go to Step 13

12

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

Is the action complete?

--

Go to Step 14

--

13

Important: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 14

--

14
  1. Turn ON the ignition, with the engine OFF.
  2. Review and record the scan tool Fail Records data.
  3. Clear the DTCs.
  4. Operate the vehicle within the parameters listed in the Conditions for Running the DTC.
  5. Using the scan tool, monitor the Specific DTC Information for DTC P0532.

Does the scan tool indicate that DTC P0532 passed?

--

System OK

Go to Step 2