Pinpoint Test A: DTC P0532:16 Or P0533:17

Climate Control System

Pinpoint Test A: DTC P0532:16 or P0533:17

Refer to Wiring Diagram Set 23, Electronic Engine Controls for schematic and connector information Electrical Diagrams.

Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information Electrical Diagrams.

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 P0532:16 (A/C Refrigerant Pressure Sensor A Circuit Low: Circuit Voltage Below Threshold)- The A/C pressure transducer inputs a feedback voltage to the PCM. This DTC sets 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 P0533:17 (A/C Refrigerant Pressure Sensor A Circuit High: Circuit Voltage Above Threshold)- The A/C pressure transducer inputs a feedback voltage to the PCM. This DTC sets 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 P0532:16 OR P0533:17

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 LH108 (GY/BN), harness side.





Is the voltage between 4.7 and 5.1 volts?

Yes
GO to A4.

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

If the voltage is greater than 5.1 volts REPAIR circuit LH108 (GY/BN) 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: PCM C175B.

- Measure the resistance between ground and A/C pressure transducer C1260-2, circuit LH108 (GY/BN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A3.

No
REPAIR circuit LH108 (GY/BN) 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

- Measure the resistance between A/C pressure transducer C1260-2, circuit LH108 (GY/BN), harness side and PCM C175B-16, circuit LH108 (GY/BN), harness side.





Is the resistance less than 5 ohms?

Yes
GO to A15.

No
REPAIR circuit LH108 (GY/BN) 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 RH108 (BN), harness side and A/C pressure transducer C1260-2, circuit LH108 (GY/BN), harness side.





Is the voltage greater than 4.7 volts?

Yes
If diagnosing DTC P0532, GO to A8.

If diagnosing DTC P0533, GO to A11.

No
GO to A5.

A5 CHECK THE SIGNAL RETURN CIRCUIT FOR VOLTAGE

- Ignition OFF.

- Disconnect: PCM C175B.

- Ignition ON.

- Measure the voltage between ground and A/C pressure transducer C1260-1, circuit RH108 (BN), harness side.





Is any voltage present?

Yes
REPAIR circuit RH108 (BN) 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 A SHORT TO THE REFERENCE VOLTAGE CIRCUIT

- Measure the resistance between A/C pressure transducer C1260-1, circuit RH108 (BN), harness side and A/C pressure transducer C1260-2, circuit LH108 (GY/BN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A7.

No
REPAIR circuit RH108 (BN) for a short to circuit LH108 (GY/BN). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A7 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN

- Ignition OFF.

- Measure the resistance between A/C pressure transducer C1260-1, circuit RH108 (BN), harness side and PCM C175B-40, circuit RH108 (BN), harness side.





Is the resistance less than 5 ohms?

Yes
GO to A15.

No
REPAIR circuit RH108 (BN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A8 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 greater than 4.7 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 A9.

A9 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT

- Ignition OFF.

- Disconnect: PCM C175B.

- Measure the resistance between A/C pressure transducer C1260-3, circuit VH442 (GN/BN), harness side and A/C pressure transducer C1260-1, circuit RH108 (BN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A10.

No
REPAIR circuit VH442 (GN/BN) for a short to circuit RH108 (BN). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A10 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR A SHORT TO GROUND

- Measure the resistance between ground and A/C pressure transducer C1260-3, circuit VH442 (GN/BN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A15.

No
REPAIR circuit VH442 (GN/BN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A11 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT 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 VH442 (GN/BN), harness side.





Is any voltage present?

Yes
REPAIR circuit VH442 (GN/BN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to A12.

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

- Measure the resistance between A/C pressure transducer C1260-3, circuit VH442 (GN/BN), harness side and A/C pressure transducer C1260-2, circuit LH108 (GY/BN), harness side.





Is the resistance greater than 10,000 ohms?

Yes
GO to A13.

No
REPAIR circuit VH442 (GN/BN) for a short to circuit LH108 (GY/BN). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A13 CHECK THE A/C PRESSURE TRANSDUCER FEEDBACK CIRCUIT FOR AN OPEN

- Measure the resistance between A/C pressure transducer C1260-3, circuit VH442 (GN/BN), harness side and PCM C175B-28, circuit VH442 (GN/BN), harness side.





Is the resistance less than 5 ohms?

Yes
GO to A14.

No
REPAIR circuit VH442 (GN/BN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

A14 CHECK THE A/C PRESSURE SENSOR (ACP_V) PCM PID WITH THE A/C PRESSURE TRANSDUCER SHORTED

NOTE: If the jumper fuse opens while carrying out this test step, repair circuit VH442 (GN/BN) for a short to ground.

- Ignition OFF.

- Connect: PCM C175B.

- Ignition ON.

- 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 C1260-1, circuit RH108 (BN), harness side and A/C pressure transducer C1260-3, circuit VH442 (GN/BN), harness side.





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 A15.

A15 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.

- 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.