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Diagnostic Test

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
  1. ACTIVE DTC 
    1. Diagnose all other DTCs before continuing.
      NOTE:

      Check for contaminants that may have damaged an O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.

    2. Start the engine.
    3. Allow the engine to reach normal operating temperature.
    4. With the scan tool, read DTCs.
      NOTE:

      It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.

      Is the DTC Active or Pending at this time?

      Yes 

      • Go To  2

      No 

  2. ECT SENSOR OPERATION 
    NOTE:

    For this test to be valid, the thermostat must be operating correctly.

    1. Ignition on, engine not running.
    2. Using the scan tool, read the Engine Coolant Temperature (ECT) Sensor value. If the engine was allowed to sit overnight (cold soak), the temperature value should be a sensible value that is somewhere close to the ambient temperature.
      NOTE:

      If engine coolant temperature is above 82°C (180°F), allow the engine to cool until 65°C (150°F) is reached.

    3. Start the Engine.
    4. During engine warm-up, monitor the ECT Sensor value. The temperature value change should be a smooth transition from start up to normal operating temperature 82°C (180°F). The value should reach at least 82°C (180°F).

      Did the ECT value increase smoothly and did it reach at least 82°C (180°F)?

      Yes 

      • Go To  3

      No 

      • Verify that there is good pin to terminal contact in the Engine Coolant Temperature Sensor and Powertrain Control Module connectors. If OK, replace the Engine Coolant Temperature Sensor.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  3. CHECKING FUEL PRESSURE 
    1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to DIAGNOSIS AND TESTING .

      Were any fuel system issues found?

      Yes 

      No 

      • Go To  4
  4. O2 SENSOR 2/1 HEATER OPERATION 
    1. Turn the ignition off.
      NOTE:

      Wait a minimum of 10 minutes to allow the O2 Sensor to cool down before continuing the test. Allow the O2 Sensor voltage to stabilize at 5.0 Volts.

      NOTE:

      Perform the following test on all O2 Sensors.

    2. Ignition on, engine not running.
    3. With the scan tool, actuate the 2/1 O2 Heater Test.
    4. Using the scan tool, monitor 2/1 O2 Sensor voltage for at least two minutes.

      Does the voltage stay above 4.5 Volts?

      Yes 

      • Verify that there is good pin to terminal contact in the O2 Sensor and Powertrain Control Module connectors. If OK, replace the O2 Sensor.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  5
  5. O2 SENSOR OPERATION 
    1. Start the engine.
    2. Allow the engine to reach normal operating temperature.
      NOTE:

      If one of the O2 Sensor Signal or Return circuits are shorted to ground the scan tool will display all O2 Sensor voltage readings low. The O2 Sensor that is shorted to ground will display a voltage reading near or at 0 Volts.

      NOTE:

      If one of the O2 Sensor Signal or Return circuits are shorted to voltage, the scan tool will display all O2 Sensor voltage readings high.

      NOTE:

      After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.

    3. Using the scan tool, monitor the O2 Sensor 2/1 voltage reading.

      Is the voltage switching between 2.5 and 3.4 Volts?

      Yes 

      • Go To  6

      No 

      • Go To  8
  6. MAP SENSOR OPERATION 
    1. Turn the ignition off.
    2. Connect a Vacuum Gauge to a Manifold Vacuum source.
    3. Start the engine.
    4. Allow the engine to idle.
      NOTE:

      If engine will not idle, maintain a constant RPM above idle.

    5. Using the scan tool, read the MAP Sensor vacuum value.

      Is the scan tool reading within one inch of Hg on the Vacuum Gauge reading?

      Yes 

      • Go To  7

      No 

      • Verify that there is good pin to terminal contact in the MAP Sensor and Powertrain Control Module connectors. If OK, replace the MAP Sensor.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. ENGINE MECHANICAL PROBLEM 
    1. Turn the ignition off.
    2. Check for any of the following conditions/mechanical problems:
      • AIR INDUCTION SYSTEM - must be free from leaks
      • ENGINE VACUUM - must be at least 13 inches in neutral
      • ENGINE VALVE TIMING - must be within specifications
      • ENGINE COMPRESSION - must be within specifications
      • ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
      • ENGINE PCV SYSTEM - must flow freely
      • TORQUE CONVERTER STALL SPEED - must be within specifications
      • POWER BRAKE BOOSTER - no internal vacuum leaks
      • FUEL - must be free of contamination
      • FUEL INJECTOR - plugged or restricted injector, control wire not connected to correct injector

      Are there any engine mechanical problems?

      Yes 

      No 

      • Go To  11
  8. O2 SENSOR 
    1. Ignition on, engine not running.
    2. Disconnect the O2 Sensor 2/1 harness connector.
    3. Using the scan tool, monitor the O2 Sensor 2/1 voltage.
    4. O2 Sensor voltage should read between 4.1 and 5.0 Volts on the scan tool with the connector disconnected.
    5. Connect a jumper between the (K43) O2 Sensor 2/1 Signal circuit and the (K902) O2 Sensor Return circuit in the O2 Sensor harness connector.
      NOTE:

      The voltage should drop from between 4.1 and 5.0 Volts to 2.5 volts with the jumper wire in place.

      Did the O2 Sensor voltage change from between 4.1 and 5.0 Volts to 2.5 volts when the jumper wire was installed?

      Yes 

      • Verify that there is good pin to terminal contact in the O2 Sensor and Powertrain Control Module connectors. If OK, replace the O2 Sensor.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  9
        NOTE:

        Remove the jumper before continuing.

  9. O2 SENSOR SIGNAL CIRCUIT 
    1. Using the scan tool, monitor all the O2 Sensor voltage readings with the jumper wire removed.
      NOTE:

      The scan tool will display all O2 Sensor voltage readings approximately 5.0 Volts when only one O2 Sensor Signal circuit is shorted to voltage.

      NOTE:

      The scan tool will display one O2 Sensor voltage close to zero and the others will read lower than normal when one O2 Sensor Signal circuit contains excessive resistance.

      Is the voltage between 4.1 and 5.0 volts?

      Yes 

      • Go To  10

      No 

      • Check all the O2 Signal circuits for a short to ground, open or short to voltage. Inspect the O2 Sensor connector and the PCM harness connector. If OK, replace and program the Powertrain Control Module in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  10. (K902) O2 SENSOR RETURN CIRCUIT 
    1. Measure the voltage on the (K902) O2 Sensor Return circuit in the O2 Sensor harness connector.

      Is the voltage at 2.5 volts?

      Yes 

      • Go To  11

      No 

      • Check the (K902) O2 Return Upstream circuit for a short to ground, open or short to voltage. Inspect the O2 Sensor connector and the PCM harness connector. If OK, replace and program the Powertrain Control Module in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  11. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensor 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 related Sensor and Powertrain Control Module connectors.
    4. Perform any Technical Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      No 

      • Replace and program the Powertrain Control Module in accordance with the service information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
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