P0533-A/C PRESSURE SENSOR CIRCUIT HIGH

For a complete wiring diagram Refer to Section 8W.

When Monitored:
Engine running and the A/C Clutch Relay energized.
Set Condition:
The A/C pressure transducer signal at the PCM goes above 4.92 volts. One trip Fault. Three good trips to turn off the MIL.

Possible Causes

(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

(C18) A/C PRESSURE SIGNAL CIRCUIT OPEN

(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (F891) 5-VOLT SUPPLY CIRCUIT

(C918) SENSOR RETURN CIRCUIT OPEN

A/C PRESSURE TRANSDUCER

FCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

1.A/C PRESSURE TRANSDUCER VOLTAGE ABOVE 4.9 VOLTS

NOTE: Make sure the A/C refrigerant System is properly charged per Service Information.

Is the voltage above 4.9 volts?

Yes

Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

2.A/C PRESSURE TRANSDUCER

Is the voltage below 1.0 volt with the jumper wire installed?

Yes

Replace the A/C Pressure Transducer.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

3.(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

Is the voltage above 0 volts?

Yes

Repair the short to battery voltage in the (C18) A/C Pressure Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

4.(C18) A/C PRESSURE SIGNAL CIRCUIT OPEN

Is the resistance below 5.0 ohms?

Yes

Repair the open in the (C18) A/C Pressure Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

5.(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (F891) 5-VOLT SUPPLY CIRCUIT

Is the resistance below 5.0 ohms?

Yes

Repair the short between the (F891) 5-volt Supply circuit and the (C18) A/C Pressure Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

6.(C918) SENSOR RETURN CIRCUIT OPEN

Is the resistance below 5.0 ohms?

Yes

Repair the open in the (C918) Sensor Return circuit
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

7.FRONT CONTROL MODULE

NOTE: Before continuing, check the FCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Were there any problems found?

Yes

Replace and program the Front Control Module per Service Information.
Perform BODY VERIFICATION TEST. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)