P0533
P0533-A/C SENDING UNIT VOLTS TOO HIGH
For complete wiring diagrams refer to Diagrams/Electrical.
- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
- Set Condition:
The circuit voltage to the ECM is above a calibrated threshold for a certain period of time.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
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. Powertrain Verification Test
No
- Go To 2
2. HARNESS OPEN
Turn the ignition off.
Disconnect the A/C pressure sending unit harness connector.
Check connectors - Clean/repair as necessary.
Turn the ignition on.
Measure the voltage between the (F855) 5-volt supply circuit and (K916) 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 (K916) return circuit to the (C918) signal circuit at the sensor harness connector.
Did P0532 set?
Yes
- Replace the A/C pressure sensor.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No
- Go To 4
4. (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO BATTERY NEGATIVE
Turn the ignition off.
Disconnect the ECM harness connectors.
Check connectors - Clean/repair as necessary.
Measure the voltage between the (F855) 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 (F855) 5-volt supply circuit shorted to the battery negative.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
5. (C918) SIGNAL CIRCUIT SHORTED TO BATTERY NEGATIVE
Measure the voltage between the (C918) signal circuit at the harness connector and battery negative.
Is the voltage less than 1 volt?
Yes
- Go To 6
No
- Repair the (C918) signal circuit shorted to the battery negative.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
6. (K916) RETURN CIRCUIT OPEN FROM ECM HARNESS CONNECTOR TO A/C HARNESS CONNECTOR
Measure the resistance of the (K916) return circuit between the sensor harness connector and the ECM harness connector.
Is the resistance less than 10 Ohms?
Yes
- Go To 7
No
- Repair the open (K916) return circuit.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
7. ECM
Reconnect the ECM harness connectors.
Turn the ignition on.
While monitoring scan tool, use a jumper wire to connect the (K916) return circuit with the (C918) signal circuit at the sensor harness connector.
Did DTC P0532 set?
Yes
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition
No
- Replace the ECM.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test