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Home >> Chrysler >> 2005 >> 300 Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Code Index, DTCS P0016 To P0121, Troubleshooting Procedure & Intermittent Condition >> Diagnosis And Testing >> P0037-O2 Sensor 1/2 Heater Circuit Low >> 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 at 5.0 volts.

    Ignition on, engine not running.

    With a scan tool, actuate the O2 1/2 Heater Test.

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

    Does the O2 Sensor 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 HEATER ELEMENT 

    Turn the ignition off.

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

    Disconnect the 1/2 O2 Sensor harness connector.

    Measure the resistance across the O2 Sensor Heater element, between the O2 Heater Control terminal and the O2 Heater ground terminal at the component.

    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 O2 Sensor Heater Element resistance 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)  O2 SENSOR 
    Fig 2: Checking O2 1/2 Heater Control Circuit
    GC0014737Courtesy of DAIMLERCHRYSLER CORP.

    Ignition on, engine not running.

    With a scan tool, actuate the O2 Heater Test with the 1/2 O2 Sensor harness connector still disconnected.

    Using a 12-volt test light connected to ground, probe the (K299) O2 1/2 Heater Control circuit in the O2 Sensor harness connector.

    Does the test light illuminate brightly and flash on and off during the actuation? 

    Yes 

    1. Replace the O2 Sensor.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .

    No 

    1. Go To step  4).
  4. 4)  (K299) O2 1/2 HEATER CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 3: Checking O2 1/2 Heater Control Circuit
    GC0014738Courtesy of DAIMLERCHRYSLER CORP.

    Turn the ignition off.

    Disconnect the PCM harness connectors.

    Measure the resistance between ground and the (K299) O2 1/2 Heater Control circuit in the O2 Sensor harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short to ground in the (K299) O2 1/2 Heater Control circuit.
    2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .

    No 

    1. Go To step  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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