P0533
P0533-A/C PRESSURE SENSOR CIRCUIT HIGHP0533-A/C Pressure Sensor Circuit High:
WHEN MONITORED
Engine running and the AC 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 (T103) 5 volt supply circuit
- (G180) Sensor return circuit open
- A/C Pressure transducer
- FCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
DIAGNOSTIC TEST
1. A/C PRESSURE TRANSDUCER VOLTAGE ABOVE 4.9 VOLTS
NOTE: Make sure the A/C refrigerant System is properly charged per Service Information.
Start the engine.
With a scan tool, read the A/C Pressure Sensor voltage.
Q: Is the voltage above 4.9 volts?
YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
2. A/C PRESSURE TRANSDUCER
Turn the ignition off.
Disconnect the A/C Pressure Transducer harness connector.
Connect a jumper wire between the (C18) A/C Pressure Signal circuit and the (G180) Sensor Return circuit in the Transducer harness connector.
Ignition on, engine not running.
With the scan tool, monitor the A/C Pressure Transducer voltage.
Q: Is the voltage below 1.0 volt with the jumper wire installed?
YES: Replace the A/C Pressure Transducer. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 3
NOTE: Remove the jumper wire before continuing.
3. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE
Turn the ignition off.
Disconnect the C1 FCM harness connector. Ignition on, engine not running.
Measure the voltage on the (C18) A/C Pressure Signal circuit in the A/C Pressure Transducer harness connector.
Q: 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. Powertrain Verification Test
NO: Go To 4
4. (C18) A/C PRESSURE SIGNAL CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the (C18) A/C Pressure Signal circuit from the A/C Pressure Transducer harness connector to the C1 FCM harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Go To 5
NO: Repair the open in the (C18) A/C Pressure Signal circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
5. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (T103) 5-VOLT SUPPLY CIRCUIT
Measure the resistance between the (C18) A/C Pressure Signal circuit and the (T103) 5 volt Supply circuit in the A/C Pressure Transducer harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Repair the short between the (T103) 5 volt Supply circuit and the (C18) A/C Pressure Signal circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 6
6. (G180) SENSOR RETURN CIRCUIT OPEN
Disconnect the C3 FCM harness connector.
Measure the resistance of the (G180) Sensor Return circuit from the A/C Pressure Sensor harness connector to the C3 FCM harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Go To 7
NO: Repair the open in the (G180) Sensor Return circuit Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
7. FRONT CONTROL MODULE
NOTE: Before continuing, check the FCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
Q: Were there any problems found?
YES: Repair as necessary. Perform BODY VERIFICATION TEST-VER 1.
NO: Replace and program the Front Control Module per Service Information. Perform BODY VERIFICATION TEST - VER 1.