Diagnostic Test

WARNING: This page is about a different car, the 2010 Dodge Charger and 2010 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

DTC IS ACTIVE
1. Start the engine and allow it to reach normal operating temperature.
  WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.
  
  NOTE: Diagnose and repair any system voltage DTCs before continuing with this test.
2. With the scan tool, select View DTCs.
  Is the status Active for this DTC?
  
  Yes
  - Go to step 2
  No
  - Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K21) IAT SIGNAL CIRCUIT SHORTED TO GROUND

Fig 1: CHECKING IAT SIGNAL CIRCUIT FOR SHORT TO GROUND
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. 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 3
  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 2: CHECKING IAT SIGNAL CIRCUIT FOR SHORT TO SENSOR GROUND 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 4
  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 CIRCUIT OR HIGH RESISTANCE

Fig 3: CHECKING IAT SIGNAL CIRCUIT FOR OPEN CIRCUIT OR HIGH RESISTANCE
Courtesy of CHRYSLER LLC

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.
1. Measure the resistance of the (K21) IAT Signal circuit between the Intake Air Temperature Sensor harness connector and the appropriate terminal of special tool #8815.
  Is the resistance below 5.0 ohms?
  
  Yes
  - Go to step 5
  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 .
INTAKE AIR TEMPERATURE SENSOR
1. Turn the ignition off.
2. Connect the Powertrain Control Module (PCM) connector.
3. Turn the ignition on.
4. With the scan tool, read the Intake Air Temperature Sensor signal voltage.
  NOTE: The sensor voltage should be approximately 5.0 volts (plus or minus .1 volt) with the connector disconnected.
  
  Does the scan tool display the voltage as described above?
  
  Yes
  - 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 .
  No
  - Go to step 6
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 .