P0532-A/C PRESSURE SENSOR CIRCUIT LOW
For a complete wiring diagram Refer to Section 8W.
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When Monitored:
Engine running, AC is learned, and AC Clutch Relay energized.
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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
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(C818) 5-VOLT SUPPLY CIRCUIT OPEN
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(C818) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
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A/C PRESSURE TRANSDUCER
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(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO GROUND
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(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (C918) A/C PRESSURE TRANSDUCER GROUND CIRCUIT
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PCM
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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 VOLT
NOTE:
Diagnose any CAN - C Communication DTCs 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
No
2.
(C818) 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 (C818) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Is the voltage between 4.5 to 5.2 volts?
Yes
No
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
No
4.
(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the C1 TIPM 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
No
5.
(C18) A/C PRESSURE SIGNAL CIRCUIT SHORTED TO THE (C918) SENSOR GROUND CIRCUIT
Measure the resistance between the (C18) A/C Pressure Signal circuit and the (C918) Sensor Ground circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 100 ohms?
Yes
No
6.
(C818) 5-VOLT SUPPLY CIRCUIT OPEN
Turn the ignition off.
Disconnect the C1 TIPM harness connector.
Measure the resistance of the (C818) 5-volt Supply circuit from the A/C Pressure Transducer harness connector to the C1 TIPM harness connector.
Is the resistance below 5.0 ohms?
Yes
No
7.
(C818) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (C818) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 100 ohms?
Yes
No
8.
TOTALLY INTEGRATED POWER MODULE
NOTE:
Before continuing, check the TIPM 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 any problems found?
Yes
No