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Pinpoint Test A: DTC P0532 or P0533




Climate Control System


Pinpoint Tests


Pinpoint Test A: DTC P0532 or P0533

Refer to Wiring Diagram Set 24, Electronic Engine Controls for schematic and connector information. Diagrams By Number

Normal Operation

Under normal operation, the A/C pressure transducer receives a ground from the PCM through circuit 359 (GY/RD). A 5-volt reference voltage is supplied to the A/C pressure transducer from the PCM through circuit 351 (BN/WH). The A/C pressure transducer sends a voltage to the PCM through circuit 1154 (WH/BK) 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

NOTE: When disconnecting and reconnecting the pressure transducer electrical connector, make sure that the connector-locking device is in place and that the locking device and connector are correctly and fully seated.

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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 C1260-2, circuit 351 (BN/WH), harness side.




- Is the voltage between 4.7 and 5.1 volts?

Yes
GO to A2.

No
REPAIR circuit 351 (BN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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A2 CHECK THE PCM SENSOR GROUND


- Measure the voltage between A/C pressure transducer C1260-1, circuit 359 (GY/RD), harness side and A/C pressure transducer C1260-2, circuit 351 (BN/WH), 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 359 (GY/RD) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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A3 CHECK THE A/C PRESSURE TRANSDUCER HIGH


- Enter the following diagnostic mode on the scan tool: A/C Pressure (ACP_PRESS) PCM PID.
- While observing the ACP_PRESS PCM PID, connect a fused jumper between A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side and A/C pressure transducer C1260-2, circuit 351 (BN/WH), harness side.




- Does the ACP_PRESS 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.

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A4 CHECK CIRCUIT 1154 (WH/BK) FOR A SHORT TO GROUND


- Ignition OFF.
- Disconnect: PCM C175b.
- Measure the resistance between ground and A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to A7.

No
REPAIR circuit 1154 (WH/BK) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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A5 CHECK THE A/C PRESSURE TRANSDUCER HIGH


- Enter the following diagnostic mode on the scan tool: A/C Pressure (ACP_PRESS) PCM PID.
- While observing the ACP_PRESS PCM PID, connect a fused jumper between A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side and A/C pressure transducer C1260-1, circuit 359 (GY/RD), harness side.




- Does the ACP_PRESS 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 A6.

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A6 CHECK CIRCUIT 1154 (WH/BK) FOR A SHORT TO VOLTAGE


- Ignition OFF.
- Disconnect: PCM C175b.
- Ignition ON.
- Measure the voltage between ground and A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side.




- Is any voltage present?

Yes
REPAIR circuit 1154 (WH/BK) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A7.

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A7 CHECK CIRCUIT 1154 (WH/BK) FOR A SHORT TO CIRCUIT 351 (BN/WH) OR 359 (GY/RD)


- Ignition OFF.
- NOTE: For DTC P0532 only.
- Measure the resistance between A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side and A/C pressure transducer C1260-1, circuit 359 (GY/RD), harness side.




- NOTE: For DTC P0533 only.
- Measure the resistance between A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side and A/C pressure transducer C1260-2, circuit 351 (BN/WH), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to A8.

No
REPAIR circuit 1154 (WH/BK) for a short to circuit 351 (BN/WH) or 359 (GY/RD). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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A8 CHECK CIRCUIT 1154 (WH/BK) FOR AN OPEN


- Measure the resistance between A/C pressure transducer C1260-3, circuit 1154 (WH/BK), harness side and PCM C175b-26, circuit 1154 (WH/BK), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to A9.

No
REPAIR circuit 1154 (WH/BK) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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A9 CHECK THE PCM CONNECTION


- Clear the DTCs.
- Disconnect all the PCM connectors.
- Check for:
- corrosion.
- pushed-out pins.
- incorrectly seated connector.
- Connect and correctly seat all the PCM connectors.
- Operate the system.
- Does the concern return?

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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