Intake Air Temperature Sensor Duty Cycle

2088 INTAKE AIR TEMPERATURE SENSOR DUTY CYCLE





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on.

- Set Condition:
The Intake Air Temperature Sensor Signal circuit voltage is below 0.12 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.Component Tests and General Diagnostics

2. INTAKE AIR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the Intake Air Temperature Sensor harness connector.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance between ground and the Intake Air Temperature Sensor Signal circuit in the Intake Air Temperature Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 3

No

- Repair the Intake Air Temperature Sensor Signal circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests

3. INTAKE AIR TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO INTAKE AIR TEMPERATURE SENSOR GROUND CIRCUIT
Measure the resistance between the Intake Air Temperature Sensor Signal circuit and the Intake Air Temperature Sensor Ground circuit in the Intake Air Temperature Sensor harness connector.
Is the resistance above 1000 ohms?

Yes

- Go to 4

No

- Repair the Intake Air Temperature Sensor Signal circuit for a short to the Intake Air Temperature Sensor Ground circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests

4. INTAKE AIR TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN CIRCUIT OR HIGH RESISTANCE
Measure the resistance of the Intake Air Temperature Sensor Signal circuit between the Intake Air Temperature Sensor harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go to 5

No

- Repair the Intake Air Temperature Sensor Signal circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

5. INTAKE AIR TEMPERATURE SENSOR
Connect the Engine Control Module (ECM) connector.
Turn the ignition on.
With the scan tool, clear DTCs.
With the scan tool, select View DTCs.

NOTE: The scan tool should display an Intake Air Temperature Sensor high voltage or open circuit DTC with the Intake Air Temperature Sensor connector disconnected.

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

Yes

- Replace the Intake Air Temperature Sensor.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go to 6

6. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Intake Air Temperature 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