P0532-A/C PRESSURE SENSOR CIRCUIT LOW
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
Engine running, AC is learned, and AC Clutch Relay energized.
- Set Condition:
The A/C pressure sensor signal voltage at the PCM goes below 0.58 of a volt for 2.6 seconds. One Trip Fault. Three good trips to turn off the MIL.
| Possible Causes |
| (K301) 5-VOLT SUPPLY CIRCUIT OPEN |
| (K301) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND |
| A/C PRESSURE TRANSDUCER |
| (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO GROUND |
| (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (K310) SENSOR GROUND CIRCUIT |
| CAN C BUS CIRCUIT OPEN OR SHORTED |
| BCM |
| PCM |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
Diagnostic Test
1. A/C PRESSURE TRANSDUCER VOLTAGE BELOW 0.6 OF A VOLTNOTE: Diagnose any CAN C Bus communication DTC's before continuing.
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.
Is the voltage below 0.6 of a volt?
Yes
- Go To 2
No
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2. (K301) 5-VOLT SUPPLY CIRCUIT
Turn the ignition off.
Disconnect the A/C Pressure Transducer harness connector.
Ignition on, engine not running.
Measure the voltage on the (K301) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Is the voltage between 4.5 to 5.2 volts?
Yes
- Go To 3
No
- Go To 6
3. A/C PRESSURE TRANSDUCER
With the scan tool, monitor the A/C Pressure Transducer voltage.
Is the voltage above 0.6 of a volt?
Yes
- Replace the A/C Pressure Transducer.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 4
4. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the C2 BCM harness connector.
Measure the resistance between ground and the (C18) A/C Pressure Signal circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (C18) A/C Pressure Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 5
5. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (K310) SENSOR GROUND CIRCUIT
Measure the resistance between the (C18) A/C Pressure Signal circuit and the (K310) Sensor ground circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short between the (K310) Sensor ground circuit and the (C18) A/C Pressure Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 8
6. (K301) 5-VOLT SUPPLY CIRCUIT OPEN
Turn the ignition off.
Disconnect the C2 BCM harness connector.
Measure the resistance of the (K301) 5-volt Supply circuit from the A/C Pressure Transducer harness connector to the C2 BCM harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 7
No
- Repair the open in the (K301) 5-volt Supply circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
7. (K301) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (K301) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (K301) 5-volt Supply circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No
- Go To 8
8. BCM
NOTE: Before continuing, check the BCM 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.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the BODY VERIFICATION TEST. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Replace and program the Body Control Module per Service Information.
- Perform the BODY VERIFICATION TEST. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)