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Diagnostic Test

WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
  1. DTC IS ACTIVE 
    NOTE:

    Diagnose and repair any Engine Coolant Temperature (ECT) sensor DTCs before proceeding with this test.

    NOTE:

    Inspect the ECT sensor and related PCM connector terminals for corrosion or damage.

    NOTE:

    Extremely cold ambient temperatures may cause this DTC to set.

    1. Turn the ignition on.
    2. With the scan tool, select View DTCs.
    3. Review DTC information.

      Is the Good Trip Counter greater than zero?

      Yes 

      No 

      • Go To  2
  2. LOW ENGINE COOLANT LEVEL 
    1. Ignition on, engine not running.
      WARNING:

      Allow the engine to cool before opening the cooling system. The system may be under pressure. Extreme burns or scalding may result. Failure to follow these instructions can result in possible serious or fatal injury.

    2. Inspect the cooling system for proper coolant level and condition.

      Were any problems found?

      Yes 

      • Inspect the vehicle for a coolant leak. Repair as necessary in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      No 

      • Go To  3
  3. THERMOSTAT 
    1. Ignition on, engine not running.
      NOTE:

      Allow the engine to cool to ambient temperature before proceeding with this test.

    2. Using the appropriate service information, determine the proper opening temperature of the thermostat.
    3. With a scan tool, read the ECT sensor value. If the engine was allowed to cool completely, the value should be approximately equal to the ambient temperature.
    4. Start the engine and allow it to reach operating temperature while monitoring the ECT sensor value. The sensor value change should be a smooth transition from start up to normal operating temperature. Monitor the actual coolant temperature with a thermometer.
      NOTE:

      As the engine warms up to operating temperature, the actual coolant temperature (thermometer reading) and the coolant temperature value on the scan tool should be relatively close. The thermostat should not open until the engine reaches the temperature specified in the Service Information.

      Does the thermostat open at the temperature specified in the Service Information?

      Yes 

      • Go To  4

      No 

      • Replace the thermostat in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  4. (K2) ECT 1 SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 1: Measuring Voltage On ECT Signal Circuit In ECT Sensor Harness Connector
    GC0120336Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Engine Coolant Temperature Sensor 1 harness connector.
    3. Disconnect the Powertrain Control Module (PCM) C2 harness connector.
    4. Turn the ignition on.
    5. Measure the voltage of the (K2) ECT 1 Signal circuit in the Engine Coolant Temperature Sensor 1 harness connector.

      Is there any voltage present?

      Yes 

      • Repair the (K2) ECT 1 Signal circuit for a short to voltage.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      No 

      • Go To  5
  5. (K2) ECT 1 SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 2: Measuring Resistance Between Ground And Sensor Signal Circuit At ECT Sensor Harness Connector
    GC0120337Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Measure the resistance between ground and the (K2) ECT 1 Signal circuit in the Engine Coolant Temperature Sensor 1 harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go To  6

      No 

      • Repair the (K2) ECT 1 Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  6. (K2) ECT 1 SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND 1 CIRCUIT 
    Fig 3: Measuring Resistance Between Signal Circuit And Sensor Ground Circuit In ECT Sensor Harness Connector
    GC0106666Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance between the (K2) ECT 1 Signal circuit and the (K900) Sensor Ground 1 circuit in the Engine Coolant Temperature Sensor 1 harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the (K2) ECT 1 Signal circuit for a short to the (K900) Sensor Ground 1 circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  7. (K2) ECT 1 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 4: Checking For Open or Excessive Resistance In ECT Signal Circuit
    GC0150064Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance in the (K2) ECT 1 Signal circuit from the ECT Sensor harness connector to the PCM C2 harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  8

      No 

      • Repair the (K2) ECT 1 Signal circuit for an open circuit or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  8. (K900) SENSOR GROUND 1 CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 5: Checking Sensor Ground Circuit Open
    GC0150066Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance of the (K900) Sensor Ground 1 circuit between the Engine Coolant Temperature Sensor 1 harness connector and the PCM C2 harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  9

      No 

      • Repair the (K900) Sensor Ground 1 for an open circuit or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  9. ENGINE COOLANT TEMPERATURE SENSOR 1 
    Fig 6: Engine Coolant Temperature Sensor Harness Connector Terminal Identification
    GC0106663Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Connect the PCM C2 harness connector.
    3. Connect a jumper wire between the (K900) Sensor Ground 1 circuit and the (K2) ECT 1 Signal circuit in the ECT Sensor 1 harness connector.
    4. Turn the ignition on.
    5. With the scan tool, read the Engine Coolant Temperature Sensor 1 Signal voltage.

      Is the voltage below 1.0 volt with the jumper wire in place?

      Yes 

      No 

      • Go To  10
  10. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Coolant Temperature Sensor 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.
    4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
    5. Look for the data to change or for the DTC to reset during the wiggle test.
    6. Perform any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No 

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