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P0533




Climate Control System

Pinpoint Test A: DTC P0532 or P0533

Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information [1][2]Diagrams By Number.

Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information [1][2]Diagrams By Number.

Normal Operation

Under normal operation, the A/C pressure transducer receives a ground from the PCM. A 5-volt reference voltage is supplied to the A/C pressure transducer from the PCM. The A/C pressure transducer then sends a voltage to the PCM to indicate the A/C pressure.

- DTC P0532 (A/C Refrigerant Pressure Sensor A Circuit Low)- The A/C pressure transducer inputs a feedback voltage to the PCM. This DTC will set if the feedback voltage is less than 0.26 volts for at least 2 seconds and the ambient air temperature is greater than 0°C (32°F).

- DTC P0533 (A/C Refrigerant Pressure Sensor A Circuit High)- The A/C pressure transducer inputs a feedback voltage to the PCM. This DTC will set if the feedback voltage is greater than 4.95 volts for at least 2 seconds and the ambient air temperature is greater than 0°C (32°F).

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- A/C pressure transducer

- PCM

PINPOINT TEST A : DTC P0532 OR P0533

A1 CHECK THE PCM OUTPUT VOLTAGE

- Ignition OFF.

- Disconnect: A/C Pressure Transducer C1260.

- Ignition ON.

- Measure the voltage between ground and A/C pressure transducer C1260-3, circuit LE423 (GN/VT), harness side.





Is the voltage between 4.7 and 5.1 volts?

Yes
GO to A2.

No
If the voltage is below 4.7 volts, REPAIR circuit LE423 (GN/VT) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the voltage is greater than 5.1 volts REPAIR circuit LE423 (GN/VT) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A2 CHECK THE PCM SENSOR GROUND

- Measure the voltage between A/C pressure transducer C1260-1, circuit RE405 (GN/WH), harness side and A/C pressure transducer C1260-3, circuit LE423 (GN/VT), harness side.





Is the voltage between 4.7 and 5.1 volts?

Yes
If diagnosing DTC P0532, GO to A3. If diagnosing DTC P0533, GO to A5.

No
REPAIR circuit RE405 (GN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A3 CHECK THE A/C PRESSURE SENSOR (ACP_V) PCM PID WITH THE A/C PRESSURE TRANSDUCER DISCONNECTED

- Enter the following diagnostic mode on the scan tool: ACP_V PCM PID.

- Observing the ACP_V PCM PID voltage.

Does the ACP_V PCM PID voltage read greater than 4 volts?

Yes
INSTALL a new A/C pressure transducer. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A4.

A4 CHECK CIRCUIT VH433 (VT/OG) FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: (5.0L, 5.4L) PCM C175B.

- Disconnect: (3.7L) PCM C1381B.

- Measure the resistance between ground and A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A5.

No
REPAIR circuit VH433 (VT/OG) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A5 CHECK CIRCUIT VH433 (VT/OG) FOR AN OPEN

- Measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and:
- For 5.0L and 5.4L, PCM C175B-31, circuit VH433 (VT/OG), harness side.

- For 3.7L, PCM C1381B-31, circuit VH433 (VT/OG), harness side.






Is the resistance less than 5 ohms?

Yes
GO to A8.

No
REPAIR circuit VH433 (VT/OG) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A6 CHECK THE A/C PRESSURE SENSOR (ACP_V) PCM PID WITH THE A/C PRESSURE TRANSDUCER SHORTED

- Enter the following diagnostic mode on the scan tool: ACP_V PCM PID.

- While observing the ACP_V PCM PID, connect a fused jumper between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and A/C pressure transducer C1260-1, circuit RE405 (GN/WH), harness side.





Does the ACP_V PCM PID voltage read less than 4.9 volts?

Yes
INSTALL a new A/C pressure transducer. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A7.

A7 CHECK CIRCUIT VH433 (VT/OG) FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: (5.0L, 5.4L) PCM C175B.

- Disconnect: (3.7L) PCM C1381B.

- Ignition ON.

- Measure the voltage between ground and A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side.





Is any voltage present?

Yes
REPAIR circuit VH433 (VT/OG) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A9.

A8 CHECK CIRCUIT VH433 (VT/OG) FOR A SHORT TO CIRCUIT RE405 (GN/WH)

- Ignition OFF.

- Measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and A/C pressure transducer C1260-1, circuit RE405 (GN/WH), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A10.

No
REPAIR circuit VH433 (VT/OG) for a short to circuit RE405 (GN/WH). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A9 CHECK CIRCUIT VH433 (VT/OG) FOR A SHORT TO CIRCUIT LE423 (GN/VT)

- Ignition OFF.

- Measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and A/C pressure transducer C1260-3, circuit LE423 (GN/VT), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A10.

No
REPAIR circuit VH433 (VT/OG) for a short to circuit LE423 (GN/VT). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A10 CHECK THE PCM CONNECTION

- Disconnect all the PCM connectors.

- Inspect the HVAC module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.


- Connect and correctly seat all the PCM connectors.

- Clear the DTCs.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new PCM. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.