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Home >> Jeep >> 2014 >> Cherokee Sport, AWD >> Repair and Diagnosis >> Engine Performance >> System >> 2.4L - DTCS B104D To P0501 >> Diagnosis And Testing >> P0140-O2 Sensor 1/2 Signal Inactive >> Diagnostic Test
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Diagnostic Test

  1. ACTIVE DTC 
    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.

    NOTE:

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

    1. Start the engine and allow the engine to reach normal operating temperature.
    2. Test drive the vehicle according to the set conditions.
    3. With the scan tool, select View DTCs.

      Is the DTC Active or Pending at this time?

      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 DIAGNOSIS AND TESTING .

      Were any exhaust leaks found?

      Yes 

      • Repair or replace the leaking exhaust parts as necessary.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  3
  3. CHECK THE (K141) O2 SENSOR 1/2 SIGNAL CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the O2 Sensor 1/2 harness connector.
    3. Ignition on, engine not running.
    4. Measure the voltage on the (K141) O2 Sensor 1/2 Signal circuit in the O2 Sensor 1/2 harness connector.

      Is the voltage between 0.09 and 0.12 volts?

      Yes 

      • Go To  4

      No 

  4. CHECK THE (K904) O2 SENSOR RETURN CIRCUIT 
    1. Measure the voltage on the (K904) O2 Sensor Return circuit at the O2 Sensor 1/2 harness connector.

      Is the voltage at 0.11 volts?

      Yes 

      • Go To  5

      No 

  5. OXYGEN SENSOR 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 1/2 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. Perform any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No