Download p0533-a/c pressure sensor circuit high

P0533-A/C PRESSURE SENSOR CIRCUIT HIGH
For a complete wiring diagram Refer to Section 8W.
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 TIPMis above a calibrated threshold for a certain
period of time.
Possible Causes
OTHER DTC'S
A/C PRESSURE SENSOR
(C18) SIGNAL CIRCUIT SHORTED TO BATTERY POSITIVE
(C818) 5-VOLT SUPPLY CIRCUIT SHORTED TO BATTERY POSITIVE
(C918) RETURN CIRCUIT OPEN FROM C7 TIPM HARNESS CONNECTOR TO A/C HARNESS
CONNECTOR
TIPM
INTERMITTENT CONDITION
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
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. (Refer to 9 - ENGINE STANDARD PROCEDURE)

Go To 2
No
2. HARNESS OPEN
Turn
the
igniti
on
off.
Disc
onne
ct the
A/C
press
ure
sendi
ng
unit
harne
ss
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

Go To 4
No
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. (Refer to 9 - ENGINE STANDARD PROCEDURE)

Go To 4
No
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

Repair the (C818) 5-volt supply circuit shorted to the battery negative.
No

Perform POWERTRAIN VERIFICATION
TEST - 6.7L. (Refer to 9 - ENGINE STANDARD PROCEDURE)
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


Repair the (C18) signal circuit shorted to the battery negative.
Perform POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 9 - ENGINE STANDARD PROCEDURE)
No
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

No
Go To 7


Repair the open (C918) return circuit.
Perform POWERTRAIN VERIFICATION
TEST - 6.7L. (Refer to 9 - ENGINE STANDARD PROCEDURE)
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). (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)


Replace the TIPM.
Perform POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 9 - ENGINE STANDARD PROCEDURE)
No