P0533

P0533-A/C PRESSURE SENSOR CIRCUIT HIGH





For a complete wiring diagram Refer to Diagrams/Electrical.

Theory of Operation


The A/C pressure sensor is mounted in the Freon circuit of the A/C system. This sensor monitors the pressure in the system. This pressure information is part of the information the C7 TIPM uses to determine if the A/C clutch should turned on or off. This information is also important to protect the Freon compressor from damage. A MIL lamp will not be lit for this fault. The customer may notice poor A/C performance.

- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.

- Set Condition:
The circuit voltage to the C7 TIPM is above a calibrated threshold for a certain period of time.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview


Diagnostic Test


1. OTHER DTC'S
Turn the ignition on.
With the scan tool, read DTCs.
Are other DTC's present?

Yes


- Repair other DTC's first.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 2



2. HARNESS OPEN




Turn the ignition off.
Disconnect the A/C pressure sending unit harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Turn the ignition on.
Measure the voltage between the (C818) 5-volt supply circuit and (C918) return circuit of the sensor harness connector.
Is the voltage between 4.5 and 5.5 volts?

Yes


- Go To 3


No


- Go To 4



3. A/C PRESSURE SENSOR




While monitoring scan tool, use a jumper wire to connect the (C918) return circuit to the (C18) signal circuit at the sensor harness connector.
Did P0532 set?

Yes


- Replace the A/C pressure sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test


No


- Go To 4



4. (C818) 5-VOLT SUPPLY CIRCUIT SHORTED TO BATTERY NEGATIVE




Turn the ignition off.
Disconnect the C7 TIPM harness connectors.

NOTE: Check connectors - Clean/repair as necessary.

Measure the voltage between the (C818) 5-volt supply circuit at the harness connector and battery negative.
Is the voltage less than 1 volt?

Yes


- Go To 5


No


- Repair the (C818) 5-volt supply circuit shorted to the battery negative.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test



5. (C18) SIGNAL CIRCUIT SHORTED TO BATTERY NEGATIVE




Measure the voltage between the (C18) signal circuit at the harness connector and battery negative.
Is the voltage less than 1 volt?

Yes


- Go To 6


No


- Repair the (C18) signal circuit shorted to the battery negative.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test



6. (C918) RETURN CIRCUIT OPEN FROM C7 TIPM HARNESS CONNECTOR TO A/C HARNESS CONNECTOR




Measure the resistance of the (C918) return circuit between the sensor harness connector and the C7 TIPM harness connector.
Is the resistance less than 10 Ohms?

Yes


- Go To 7


No


- Repair the open (C918) return circuit.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test



7. TIPM




Reconnect the C7 TIPM harness connectors.
Turn the ignition on.
While monitoring scan tool, use a jumper wire to connect the (C918) return circuit with the (C18) signal circuit at the sensor harness connector.
Did DTC P0532 set?

Yes


- Refer to the INTERMITTENT CONDITION - DIESEL Symptom (Diagnostic Procedure). Intermittent Condition


No


- Replace the TIPM.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test