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P012C







P012C-TURBO INLET AIR PRESSURE SENSOR CIRCUIT LOW





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on.

- Set Condition:
The (K68) Inlet Air Pressure Sensor Signal circuit voltage is below 0.35 volt for 2.0 seconds.





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

Diagnostic Test

1. DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, Clear DTCs in the Engine Control Module (ECM).
Monitor the scan tool for at least two minutes.
Cycle the ignition key off and on several times, leaving the ignition on for at least 10 seconds at a time.
Start the engine.
Allow the engine to reach normal operating temperature.
With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go To 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Intermittent Condition

2. (K668) INLET AIR PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT VOLTAGE




Turn the ignition off.
Disconnect the Inlet Air Pressure Sensor harness connector.
Turn the ignition on.
Measure the voltage of the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit in the Inlet Air Pressure Sensor harness connector.
Is the voltage above 4.5 volts?

Yes

- Go to 6

No

- Go to 3

3. (K668) INLET AIR PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance between ground and the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit in the Inlet Air Pressure Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 4

No

- Repair the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests

4. (K668) INLET AIR PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO (K900) INLET AIR PRESSURE SENSOR GROUND CIRCUIT




Measure the resistance between the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit and the (K900) Inlet Air Pressure Sensor Ground circuit in the Inlet Air Pressure Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 5

No

- Repair the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit for a short to the (K900) Inlet Air Pressure Sensor Ground circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests

5. (K668) INLET AIR PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE




Measure the resistance of the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit between the Inlet Air Pressure Sensor harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go to 10

No

- Repair the (K668) Inlet Air Pressure Sensor 5 Volt Supply circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

6. INLET AIR PRESSURE SENSOR
Turn the ignition on.
With the scan tool, Clear DTCs.
With the scan tool, select View DTCs.

NOTE: The scan tool should display a Inlet Air Pressure Sensor high voltage or open DTC with the Inlet Air Pressure Sensor connector disconnected.

Does the scan tool display the DTC(s) as described above?

Yes

- Replace the Inlet Air Pressure Sensor.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go to 7

7. (K68) INLET AIR PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance between ground and the (K68) Inlet Air Pressure Sensor Signal circuit in the Inlet Air Pressure Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 8

No

- Repair the (K68) Inlet Air Pressure Sensor Signal circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests

8. (K68) INLET AIR PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO (K900) INLET AIR PRESSURE SENSOR GROUND CIRCUIT




Measure the resistance between the (K68) Inlet Air Pressure Sensor Signal circuit and the (K900) Inlet Air Pressure Sensor Ground circuit in the Inlet Air Pressure Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 9

No

- Repair the (K68) Inlet Air Pressure Sensor Signal circuit for a short to the (K900) Inlet Air Pressure Sensor Ground circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests

9. (K68) INLET AIR PRESSURE SENSOR SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE




Measure the resistance of the (K68) Inlet Air Pressure Sensor Signal circuit between the Inlet Air Pressure Sensor harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go to 10

No

- Repair the (K68) Inlet Air Pressure Sensor Signal circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

10. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Inlet Air Pressure Sensor and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Replace the Engine Control Module (ECM).
- Perform the ECM Verification Test Ver. 1. Verification Tests

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