Diagnostic Test

DTC IS ACTIVE
NOTE: Diagnose any CAN - C Communication DTCs before continuing.
1. Turn the ignition off.
2. If possible, allow the vehicle to sit with the ignition off for more than 480 minutes in an environment where the temperature is consistent and above - 7°C (19.4°F).
3. Test drive the vehicle. The vehicle must exceed 48 km/h (30 mph) during the test drive. Do not cycle the ignition off when the test drive is completed.
4. With a scan tool, select View DTCs.
  Is the status Active or Pending for this DTC?
  
  Yes
  - Go to step 3
  No
  - Go to step 2
INTAKE AIR TEMPERATURE
1. Turn the ignition off.
2. Allow the vehicle to sit with the ignition off in an environment where the temperature is consistent and above - 7°C (19.4°F) until the engine coolant temperature is equal to ambient temperature.
3. Turn the ignition on.
4. With a scan tool, compare the AAT, ECT, and IAT sensor values.
  Is the Intake Air Temperature Sensor value within 10°C (18°F) of the other two sensor values?
  
  Yes
  - Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
  No
  - Go to step 3
(K21) IAT SIGNAL CIRCUIT SHORTED TO VOLTAGE

Fig 1: Checking IAT Signal Circuit
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the Intake Air Temperature Sensor connector.
3. Disconnect the Powertrain Control Module (PCM) connector.
4. Turn the ignition on.
5. Measure the voltage of the (K21) IAT Signal circuit in the Intake Air Temperature Sensor harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the (K21) IAT Signal circuit for a short to voltage.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Go to step 4
(K21) IAT SIGNAL CIRCUIT SHORTED TO GROUND

Fig 2: Checking IAT Signal Circuit
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Measure the resistance between ground and the (K21) IAT Signal circuit in the Intake Air Temperature Sensor harness connector.
  Is the resistance above 100 ohms?
  
  Yes
  - Go to step 5
  No
  - Repair the (K21) IAT Signal circuit for a short to ground.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K21) IAT SIGNAL CIRCUIT SHORTED TO (K900) SENSOR GROUND CIRCUIT

Fig 3: Checking IAT Signal Circuit
Courtesy of CHRYSLER LLC
1. Measure the resistance between the (K21) IAT Signal circuit and the (K900) Sensor Ground circuit in the Intake Air Temperature Sensor harness connector.
  Is the resistance above 100 ohms?
  
  Yes
  - Go to step 6
  No
  - Repair the (K21) IAT Signal circuit for a short to the (K900) Sensor Ground circuit.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K21) IAT SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

Fig 4: Checking IAT Signal Circuit
Courtesy of CHRYSLER LLC

NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
1. Measure the resistance of the (K21) IAT Signal circuit between the Intake Air Temperature Sensor harness connector and the Powertrain Control Module (PCM) harness connector.
  Is the resistance below 5.0 ohms?
  
  Yes
  - Go to step 7
  No
  - Repair the (K21) IAT Signal circuit for an open circuit or high resistance.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K900) SENSOR GROUND CIRCUIT OPEN OR HIGH RESISTANCE

Fig 5: Checking Ground Circuit
Courtesy of CHRYSLER LLC

NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
1. Measure the resistance of the (K900) Sensor Ground circuit between the Intake Air Temperature Sensor harness connector and the Powertrain Control Module (PCM) harness connector.
  Is the resistance below 5.0 ohms?
  
  Yes
  - Go to step 8
  No
  - Repair the (K900) Sensor Ground for an open circuit or high resistance.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
INTAKE AIR TEMPERATURE SENSOR SIGNAL VOLTAGE

Fig 6: Checking IAT Signal Circuit
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Connect the Powertrain Control Module (PCM) connector.
3. Connect a jumper wire between the (K900) Sensor Ground circuit and the (K21) IAT Signal circuit in the Intake Air Temperature Sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, read the Intake Air Temperature Sensor signal voltage.
  Is the voltage below 1.0 volt with the jumper wire in place?
  
  Yes
  - Go to step 9
  No
  - Go to step 10
INTAKE AIR TEMPERATURE SENSOR
1. Turn the ignition off.
2. Inspect the wiring and connectors between the Intake Air Temperature Sensor and the Powertrain Control Module (PCM).
3. Look for any chafed, pierced, pinched, or partially broken wires.
4. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Replace the Intake Air Temperature Sensor in accordance with the Service Information.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Intake Air Temperature Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Refer to any Technical Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
  - Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .