Diagnostic Test

DTC IS ACTIVE
1. Turn the ignition on.
2. With a scan tool, select View DTCs. Record DTC and Freeze Frame information.
3. Start the engine and allow it to idle for at least 60 seconds.
  WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hand near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.
4. With a 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. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
(K243) O2 2/2 SIGNAL CIRCUIT
1. Turn the ignition off.
2. Disconnect the 2/2 Oxygen Sensor harness connector.
3. Turn the ignition on.
4. With a scan tool, read the 2/2 Oxygen Sensor voltage.
  Is the 2/2 Oxygen Sensor voltage above 4.8 volts?
  
  Yes
  - Go to 3
  No
  - Go to 5
2/2 OXYGEN SENSOR

Fig 1: Measuring Voltage On O2 Sensor Return Circuit In Oxygen Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Measure the voltage on the (K904) O2 Return (Downstream) circuit in the 2/2 O2 Sensor harness connector.
  Is the voltage between 2.40 and 2.60 volts?
  
  Yes
  - Replace the 2/2 O2 Sensor.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Go to 4
(K904) O2 RETURN (DOWNSTREAM) CIRCUIT SHORTED TO GROUND

Fig 2: Measuring Resistance Between Ground And O2 Sensor Return Circuit In Oxygen Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the C1 Powertrain Control Module (PCM) harness connector.
3. Measure the resistance between ground and the (K904) O2 Return (Downstream) circuit in the 2/2 Oxygen Sensor harness connector.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the short to ground in the (K904) O2 Return (Downstream) circuit.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Go to 5
(K243) O2 2/2 SIGNAL CIRCUIT SHORTED TO GROUND

Fig 3: Measuring Resistance Between Ground And O2 Sensor Signal Circuit In Oxygen Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Measure the resistance between ground and the (K243) O2 2/2 Signal circuit in the 2/2 O2 Sensor harness connector.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the short to ground in the (K243) O2 2/2 Signal circuit.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Go to 6
(K243) O2 2/2 SIGNAL CIRCUIT SHORTED TO THE (K904) O2 RETURN (DOWNSTREAM) CIRCUIT

Fig 4: Measuring Resistance Between O2 Sensor Signal Circuit And O2 Sensor Return Circuit In Oxygen Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Measure the resistance between the (K243) O2 2/2 Signal circuit and the (K904) O2 Return (Downstream) circuit in the 2/2 Oxygen Sensor harness connector.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the short between the (K243) O2 2/2 Signal circuit and the (K904) O2 Return (Downstream) circuit.
  - Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Go to 7
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 2/2 Oxygen 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. 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 .