P0532
P0532-A/C PRESSURE SENSOR CIRCUIT LOWP0532-A/C Pressure Sensor Circuit Low:
WHEN MONITORED
Engine running, AC is learned, and AC Clutch Relay energized.
SET CONDITION
The A/C pressure transducer 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
- (F891) 5-volt supply circuit open
- (F891) 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 (C918) sensor return circuit
- Front control module
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Diagnostic Test
1. A/C PRESSURE TRANSDUCER VOLTAGE BELOW 0.6 OF A VOLT
NOTE: Make sure the A/C refrigerant System is properly charged.
Start the engine.
With a scan tool, read the A/C Pressure Sensor voltage.
Q: Is the voltage below 0.6 of a volt?
YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Component Tests and General Diagnostics
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
2. (F891) 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 (F891) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Q: 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.
Q: Is the voltage above 0.6 of a volt?
YES: Replace the A/C Pressure Transducer. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 4
4. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the C1 FCM harness connector.
Measure the resistance between ground and the (C18) A/C Pressure Signal circuit in the A/C Pressure Transducer harness connector.
Q: 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. Powertrain Verification Test
NO: Go To 5
5. (C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (C918) SENSOR RETURN CIRCUIT
Disconnect the IPM FCM harness connector.
Measure the resistance between the (C18) A/C Pressure Signal circuit and the (C918) Sensor Return circuit in the A/C Pressure Transducer harness connector.
Q: Is the resistance below 100 ohms?
YES: Repair the short between the (C918) Sensor Return circuit and the (C18) A/C Pressure Signal circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 8
6. (F891) 5-VOLT SUPPLY CIRCUIT OPEN
Turn the ignition off.
Disconnect the C1 FCM harness connector.
Measure the resistance of the (F891) 5-volt Supply circuit from the A/C Pressure Transducer harness connector to the C1 FCM harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Go To 7
NO: Repair the open in the (F891) 5-volt Supply circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
7. (F891) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (F891) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Q: Is the resistance below 100 ohms?
YES: Repair the short to ground in the (F891) 5-volt Supply circuit. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 8
8. FRONT CONTROL MODULE
NOTE: Before continuing, check the FCM 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.
Q: Were there any problems found?
YES: Repair as necessary. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test
NO: Replace and program the Front Control Module. Perform BODY VERIFICATION TEST VER - 1. Body Verification Test