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Home >> Chrysler >> 2006 >> 300 Base, 42RLE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - DTCS P0122 To P0175 >> Diagnosis And Testing >> P0155-O2 Sensor 2/1 Heater Performance >> Diagnostic Test
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Diagnostic Test

  1. 1)  O2 SENSOR HEATER OPERATION 

    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 the scan tool, monitor 2/1 O2 Sensor voltage for at least 2 minutes.

    Does the voltage stay above 4.5 volts? 

    Yes 

    1. Go To  2).

    No 

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

    Turn the ignition off.

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

    Disconnect the 2/1 O2 Sensor harness connector.

    Measure the resistance of the O2 Heater Element across the O2 Sensor connector between the O2 Heater Control terminal and the O2 Heater ground terminal.

    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  3).

    No 

    1. Replace the O2 Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .
  3. 3)  (K199) O2 2/1 HEATER CONTROL CIRCUIT HIGH RESISTANCE 

    Disconnect the O2 harness connectors.

    With the scan tool, actuate the O2 Heater.

    Using a 12-volt test light connected ground, probe the (K199) O2 2/1 Heater Control circuit from the O2 harness connector.

    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Does the test light illuminate brightly? 

    Yes 

    1. Go To  4).

    No 

    1. Repair the excessive resistance in the (K199) O2 2/1 Heater Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  4. 4)  (Z904) O2 SENSOR HEATER GROUND CIRCUIT HIGH RESISTANCE 

    Using a 12-volt test light connected battery voltage, probe the (Z904) O2 Heater ground circuit in the O2 Sensor harness connector.

    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Does the test light illuminate brightly? 

    Yes 

    1. Go To  5).

    No 

    1. Repair the excessive resistance in the (Z904) O2 Heater ground circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  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 POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
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