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HOMESERVICE MANUALSJEEP2014GRAND CHEROKEE LAREDO, AWDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT VARIANT/TRIMSECTION 29 (6.4L - DTCS P000B TO P0300)DIAGNOSIS AND TESTINGP0051-O2-SENSOR 2/1 HEATER CIRCUIT LOWDIAGNOSTIC TEST
2014 Jeep Grand Cherokee Laredo, AWD

Diagnostic Test

2014 Jeep Grand Cherokee Laredo, AWDSECTION Diagnostic Test
WARNING: This page is about a different variant/trim than selected.
  1. ACTIVE DTC 
    1. Start the engine and allow it to idle for at least 60 seconds.
      WARNING:

      When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

    2. With the scan tool, read the active DTCs.

      Is the DTC Active at this time?

      Yes 

      • Go To  2

      No 

  2. O2 SENSOR 2/1 HEATER ELEMENT 
    1. Turn the ignition off.
      NOTE:

      Allow the O2 Sensor to cool down to room temperature.

    2. Disconnect the O2 Sensor 2/1 harness connector.
    3. Measure the resistance across the O2 Sensor 2/1 Heater element, between the Heater Control terminal and the Heater ground terminal at the component.
      NOTE:

      O2 Sensor 2/1 Heater Element resistance values should be measured at 21.1°C (70°F). The resistance value will vary with different temperature values.

      Is the O2 Sensor 2/1 Heater Element resistance between 2.0 and 30.0 Ohms?

      Yes 

      • Go To  3

      No 

      • Verify that there is good pin to terminal contact in the 2/1 O2 Sensor and Powertrain Control Module connectors. If OK, replace the O2 Sensor. Refer to SENSOR, OXYGEN, REMOVAL .
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  3. CHECK THE (K199) O2 SENSOR 2/1 HEATER CONTROL CIRCUIT FOR A SHORT TO GROUND 
    Fig 1: Checking O2 Sensor Heater Control Circuit For Short To Ground
    GC0138737Courtesy of CHRYSLER GROUP, LLC
    1. Disconnect the PCM C2 harness connector.
    2. Measure the resistance between ground and the (K199) O2 Sensor 2/1 Heater Control circuit in the O2 Sensor harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Repair the short to ground in the (K199) O2 Sensor 2/1 Heater Control circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  4
  4. CHECK FOR EXCESSIVE RESISTANCE IN THE (K199) O2 SENSOR 2/1 HEATER CONTROL CIRCUIT 
    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 the GPEC Diagnostic Adaptor to perform the diagnosis.

    1. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
    2. Measure the resistance of the (K199) O2 Sensor 2/1 Heater Control circuit between the O2 Sensor 2/1 harness connector and the GPEC Adaptor.

      Is the resistance below 0.5 Ohm?

      Yes 

      • Go To  5

      No 

      • Repair the excessive resistance in the (K199) O2 Sensor 2/1 Heater Control circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 2/1 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. Verify that there is good pin to terminal contact in the Oxygen Sensor 2/1 and Powertrain Control Module connectors.
    4. Perform any Technical Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      No 

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.