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Pinpoint Test A: DTC P0532 or P0533




Climate Control System

Pinpoint Test A: DTC P0532 or P0533

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 Pressure Refrigerant Sensor A Circuit Low)- The A/C pressure transducer inputs a voltage to the PCM. If the voltage is below the calibrated level, this DTC sets.

- DTC P0533 (A/C Pressure Refrigerant Sensor A Circuit High)- The A/C pressure transducer inputs a voltage to the PCM. If the voltage is above the calibrated level, this DTC sets.

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 LE424 (YE/GN), harness side.





Is the voltage between 4.7 and 5.1 volts?

Yes
GO to A4.

No
If the voltage is below 4.7 volts, GO to A2.

If the voltage is greater than 5.1 volts REPAIR circuit LE424 (YE/GN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A2 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: For 3.7L, PCM C175B.

- Disconnect: For 3.5L, PCM C1381B.

- Measure the resistance between ground and A/C pressure transducer C1260-3, circuit LE424 (YE/GN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A3.

No
REPAIR circuit LE424 (YE/GN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A3 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR AN OPEN

- 3.7L only





For 3.7L only, measure the resistance between A/C pressure transducer C1260-3, circuit LE424 (YE/GN), harness side and PCM C175B-64, circuit LE424 (YE/GN), harness side.

- 3.5L only





For 3.5L only, measure the resistance between A/C pressure transducer C1260-3, circuit LE424 (YE/GN), harness side and PCM C1381B-52, circuit LE424 (YE/GN), harness side.

Is the resistance less than 5 ohms?

Yes
GO to A13.

No
REPAIR circuit LE424 (YE/GN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A4 CHECK THE PCM SENSOR GROUND

- Measure the voltage between A/C pressure transducer C1260-1, circuit RE407 (YE/VT), harness side and A/C pressure transducer C1260-3, circuit LE424 (YE/GN), harness side.





Is the voltage greater than 4.7 volts?

Yes
If diagnosing DTC P0532, GO to A7.

If diagnosing DTC P0533, GO to A10.

No
GO to A5.

A5 CHECK THE SIGNAL RETURN CIRCUIT FOR VOLTAGE

- Measure the voltage between ground and A/C pressure transducer C1260-1, circuit RE407 (YE/VT), harness side.





Is any voltage present?

Yes
If the voltage is 5.1 volts or less, REPAIR circuit RE407 (YE/VT) for a short to circuit LE424 (YE/GN). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the voltage is greater than 5.1 volts REPAIR circuit RE407 (YE/VT) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A6.

A6 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: For 3.7L, PCM C175B.

- Disconnect: For 3.5L, PCM C1381B.

- 3.7L only





For 3.7L only, measure the resistance between A/C pressure transducer C1260-1, circuit RE407 (YE/VT), harness side and PCM C175B-58, circuit RE407 (YE/VT), harness side.

- 3.5L only





For 3.5L only, measure the resistance between A/C pressure transducer C1260-1, circuit RE407 (YE/VT), harness side and PCM C1381B-56, circuit RE407 (YE/VT), harness side.

Is the resistance less than 5 ohms?

Yes
GO to A13.

No
REPAIR circuit RE407 (YE/VT) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A7 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: PCM DataLogger.

- While observing the ACP_V PCM PID, connect a fused jumper between A/C pressure transducer C1260-3, circuit LE424 (YE/GN), harness side and A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side.





Does the ACP_V PCM PID voltage read between 4.7 and 5.1 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 A8.

A8 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT

- Ignition OFF.

- Disconnect: For 3.7L, PCM C175B.

- Disconnect: For 3.5L, PCM C1381B.

- Measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and A/C pressure transducer C1260-1, circuit RE407 (YE/VT), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A9.

No
REPAIR circuit VH433 (VT/OG) for a short to circuit RE407 (YE/VT). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A9 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR AN OPEN

- 3.7L only





For 3.7L only, measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and PCM C175B-37, circuit VH433 (VT/OG), harness side.

- 3.5L only





For 3.5L only, measure the resistance between A/C pressure transducer C1260-2, circuit VH433 (VT/OG), harness side and PCM C1381B-31, circuit VH433 (VT/OG), harness side.

Is the resistance less than 5 ohms?

Yes
GO to A13.

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

A10 CHECK THE A/C PRESSURE TRANSDUCER

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

- Observe the A/C Pressure Sensor (ACP_V) PCM PID voltage.

Does the ACP_V PCM PID voltage read 0 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 A11.

A11 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR VOLTAGE

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





Is any voltage present?

Yes
GO to A12.

No
GO to A13.

A12 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: For 3.7L, PCM C175B.

- Disconnect: For 3.5L, 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
REPAIR circuit VH433 (VT/OG) for a short to circuit LE424 (YE/GN). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A13 CHECK THE PCM CONNECTION

- Disconnect all the PCM connectors.

- Inspect the PCM 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.

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