DTC Troubleshooting: P0533 (191)

DTC P0533:  A/C Pressure Sensor Circuit High Voltage


NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

1.Start the engine, and let it idle.

2.Turn the blower switch on.

3.Turn the A/C switch on.

4.Check the A/C PRESSURE SENSOR in the DATA LIST with the HDS.

Is there about 4.75 V or more?


YES - Go to 5.


NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/C pressure sensor and the ECM/PCM.n


5.Turn the ignition switch OFF.

6.Disconnect the A/C pressure sensor 3P connector.

7.Connect A/C pressure sensor 3P connector terminals No. 2 and No. 3 with a jumper wire.

 

8.Turn the ignition switch ON (II).

9.Check the A/C PRESSURE SENSOR in the DATA LIST with the HDS.

Is there about 4.75 V or more?


YES - Go to 10.


NO - Go to 22.


10.Turn the ignition switch OFF.

11.Remove the jumper wire from the A/C pressure sensor 3P connector.

12.Turn the ignition switch ON (II).

13.Measure voltage between A/C pressure sensor 3P connector terminals No. 1 and No. 3.

 

Is there about 5 V?


YES - Go to 14.


NO - Go to 18.

14.Turn the ignition switch OFF.

15.Jump the SCS line with the HDS.

16.Disconnect ECM/PCM connector A (44P).

17.Check for continuity between A/C pressure sensor 3P connector terminal No. 2 and ECM/PCM connector terminal A16.

 

Is there continuity?


YES - Go to 32.


NO - Repair open in the wire between the ECM/PCM (A16) and the A/C pressure sensor, then go to 24.

18.Turn the ignition switch OFF.

19.Jump the SCS line with the HDS.

20.Disconnect ECM/PCM connector A (44P).

21.Check for continuity between A/C pressure sensor 3P connector terminal No. 3 and ECM/PCM connector terminal A9.

 

Is there continuity?


YES - Go to 32.


NO - Repair open in the wire between the ECM/PCM (A9) and the A/C pressure sensor, then go to 24.

22.Turn the ignition switch OFF.

23.Replace the A/C pressure sensor.

24.Reconnect all connectors.

25.Turn the ignition switch ON (II).

26.Reset the ECM/PCM with the HDS.

27.Do the ECM/PCM idle learn procedure.

28.Start the engine, and let it idle.

29.Turn the blower switch on.

30.Turn the A/C switch on.

31.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0533 is indicated, check for poor connections or loose terminals at the A/C pressure sensor and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n

32.Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.

33.Start the engine, and let it idle.

34.Turn the blower switch on.

35.Turn the A/C switch on.

36.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0533 is indicated, check for poor connections or loose terminals at the A/C pressure sensor and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.n