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Home >> Chrysler >> 2005 >> 300 Base >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P0122 To P0175 >> Diagnosis And Testing >> P0161-O2 Sensor 2/2 Heater Performance >> Diagnostic Test
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Diagnostic Test

  1. 1)  O2 SENSOR HEATER OPERATION 
    Fig 1: SCAN TOOL (STARSCAN)
    GC0013164Courtesy of DAIMLERCHRYSLER CORP.

    Turn the ignition off.

    NOTE: Wait a minimum of 8 minutes to allow the O2 Sensor to cool down before continuing the test. Allow the O2 Sensor voltage to stabilize between 4.6 and 5.0 volts.

    Ignition on, engine not running.

    With a scan tool, actuate the O2 Heater Test.

    With a scan tool, monitor 2/2 O2 Sensor voltage for at least 2 minutes.

    Does the voltage stay above 4.5 volts? 

    Yes 

    1. Go To step  2).

    No 

    1. Refer to INTERMITTENT CONDITION .
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
  2. 2)  O2 SENSOR HEATER ELEMENT 

    Turn the ignition off.

    NOTE: Allow the O2 sensor to cool down to room temperature.

    Disconnect the O2 Sensor harness connector.

    Measure the resistance of the 2/2 O2 Heater Element, between the O2 Heater Control terminal and the O2 Heater ground terminal in the O2 Sensor connector.

    NOTE: O2 Heater Element resistance values should be measured at 70°F (21.1°C). The resistance value will vary with different temperature values.

    Is the resistance of the O2 Sensor Heater Element between 2.0 and 30.0 ohms? 

    Yes 

    1. Go To step  3).

    No 

    1. Replace the O2 Sensor.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
  3. 3)  (K399) O2 2/2 HEATER CONTROL CIRCUIT OPEN 
    Fig 2: Checking Right Rear O2 Sensor Heater Control Circuit
    GC0014753Courtesy of DAIMLERCHRYSLER CORP.

    Disconnect the PCM harness connectors.

    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.

    Measure the resistance of the (K399) O2 2/2 Heater Control circuit from the O2 harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 0.5 of an ohm? 

    Yes 

    1. Go To step  4).

    No 

    1. Repair the excessive resistance in the (K399) O2 2/2 Heater Control circuit.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
  4. 4)  (Z902) O2 2/2 HEATER GROUND CIRCUIT OPEN 
    Fig 3: Checking Right Rear O2 Sensor Heater Ground Circuit
    GC0014751Courtesy of DAIMLERCHRYSLER CORP.

    Measure the resistance between ground and the (Z902) O2 2/2 Heater ground circuit in the O2 Sensor harness connector.

    Is the resistance below 0.5 of an ohm? 

    Yes 

    1. Go To step  5).

    No 

    1. Repair the excessive resistance in the (Z902) O2 2/2 Heater ground circuit.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
  5. 5)  PCM 
    NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

    Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .

    No 

    1. Replace and program the Powertrain Control Module. Refer to MODULE-POWERTRAIN CONTROL .
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
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