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Home >> Dodge and Ram >> 2021 >> Durango SXT Plus, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> 3.6L - DTCS P2172 To U01B0 >> DTC Troubleshooting >> P2273-O2 Sensor 2/2 Signal Biased Rich >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    NOTE:

    Check for contaminants that may have damaged the O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.

    NOTE:

    After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.

    1. Start the engine.
    2. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    3. With the scan tool, read DTCs and record on the repair order.
      NOTE:

      It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECKING THE EXHAUST SYSTEM FOR LEAKS 
    1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .

      Were any exhaust leaks found?

      Yes 

      No 

      • Go To  3
  3. CHECK THE (K243) O2 SENSOR 2/2 SIGNAL CIRCUIT 
    1. Turn the ignition off
    2. Disconnect the O2 Sensor 2/2 harness connector.
    3. Turn the ignition on.
    4. Measure the voltage on the (K243) O2 Sensor 2/2 Signal circuit in the O2 Sensor 2/2 harness connector.

      Is the voltage between 4.1 and 5.0 volts?

      Yes 

      • Go To  4

      No 

      • Check the (K243) O2 Sensor 2/2 Signal circuit for a short to ground, open, or short to voltage. If no problems are found, replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. CHECK THE (K904) O2 SENSOR 2/2 RETURN CIRCUIT VOLTAGE VALUE 
    1. Measure the voltage on the (K904) O2 Return Downstream circuit in the O2 Sensor 2/2 harness connector.

      Is the voltage at 2.5 volts?

      Yes 

      • Go To  5

      No 

      • Check the (K904) O2 Sensor 2/2 Return circuit for a short to ground, open, or short to voltage. If no problems are found, replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK THE O2 SENSOR FOR PROPER OPERATION 
    NOTE:

    Check for signs of contaminants that may have damaged the O2 Sensor, such as contaminated fuel, unapproved silicone, oil and coolant.

    1. Using the appropriate SYSTEM WIRING DIAGRAM/schematic as a guide, inspect the wiring and connectors between the O2 Sensor 2/2 and the Powertrain Control Module (PCM).
      • Look for any chafed, pierced, pinched, or partially broken wires.
      • Look for broken, bent, pushed out or corroded terminals.
      • Verify that there is good pin to terminal contact in the O2 Sensor 2/2 and Powertrain Control Module connectors.
      • Perform any Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No