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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> 2.0L - DTCS P0261-00 To P046C-00 >> DTC Troubleshooting >> P0338-00-Crankshaft Position Sensor "A" Circuit High >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR APPLICABLE SERVICE BULLETINS 
    1. Check for any Service Bulletins that may apply for this issue.

      Were any Service Bulletins applicable?

      Yes 

      • Perform the applicable Service Bulletin. Erase the DTC and perform the verification test.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  2
  2. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Powertrain Control Module (PCM) DTCs and Freeze Frame Data and record on the repair order.
    2. Using the recorded Freeze Frame Data and the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
      NOTE:

      If the vehicle starts and runs, wiggle test the wiring in an attempt to duplicate the problem or set the fault.

    3. With the scan tool, read PCM DTCs.

      Is the DTC stored, active or pending?

      DTC is stored 

      • Go To  3

      DTC is active or pending 

      • Go To  5
  3. WIRE HARNESS AND CKP SENSOR INSPECTION 
    1. Turn the ignition off.
    2. Verify that the CKP Sensor harness connector is fully seated and the primary lock is engaged at the sensor before disconnecting.
    3. Start the engine and wiggle test the wiring harness and connectors in attempt to duplicate the problem.
    4. Turn the ignition off.
    5. Disconnect the harness connectors at the PCM and Crank Sensor and inspect for wire chaffing or rub conditions, terminals pushed out, bent terminals, water in the connector cavities or presence of corrosion on the terminals of the connectors or components.
    6. Visually inspect the mounting area of Crank Sensor for debris, damage or a loose sensor.

      Were any problems found?

      Yes 

      No 

      • Go To  4
  4. CHECK THE VEHICLE REPAIR HISTORY 
    1. Check the history of the vehicle for previous Crank Sensor related DTCs within the past 90 days. Verify if the Crank Sensor was replaced during the visit.

      Did the repair history show that the vehicle was in dealership for a crank sensor fault within the past 90 days?

      Yes and the Crank Sensor was replaced on previous visit 

      • Wiggle test the wiring harness and connectors again and try to duplicate the issue. If not able to duplicate, remove the Crank Sensor and visually inspect the sensor mounting location for damage or foreign material.
      • Inspect the target wheel for any signs of damage by placing a bore scope into the CKP Sensor bore and manually rotate the engine slowly using a wrench on the crank damper bolt. For stamped steel targets, pay close attention to the light reflection of the bore scope light on each tooth. If a tooth is bent, the reflection (bright spot) will move in relation to the reflection of the other teeth that are not bent. The light reflection will remain in the same location on each tooth if none of the teeth are bent. For powder metal targets, look for any tooth that is dull or does not shine as compared to the other teeth. The rough surface that remains from a tooth that has broken off appears to be dull or non-reflective.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      Yes and the Crank Sensor was not replaced on the last visit 

      • Replace the Crank Position Sensor in accordance with the Service Information. With the scan tool, perform "The Phonic Wheel Reset  " Procedure.
        NOTE:

        "The Phonic Wheel Reset"  procedure must be performed every time there has been a repair or replacement made to a CMP Sensor, CKP sensor, flywheel, valvetrain, timing chain or gears. Failure to do so can cause a misfire fault to set.

      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Test complete. Reconnect the harness connectors, and erase the DTC. The most likely cause was a poor connection at one of the harness connectors.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK FOR OTHER DTCS 
    1. Refer to the recorded DTCs.

      Are there any 5-Volt Reference DTCs active or pending?

      Yes 

      No 

      • Go To  6
  6. CHECK THE (F855) 5-VOLT SUPPLY CIRCUIT VOLTAGE 
    1. Turn the ignition off.
    2. Disconnect the CKP Sensor harness connector.
    3. Turn the ignition on.
    4. Measure the voltage on the (F855) 5-Volt Supply circuit at the CKP Sensor harness connector.

      Is the voltage between 4.8 and 5.2 volts?

      Yes 

      • Go To  7

      No - voltage is below 4.8 volts: 

      No - voltage is above 5.2 volts: 

      • Repair the 5-Volt Supply circuit for a short to voltage.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. CHECK THE (K24) CKP SIGNAL CIRCUIT VOLTAGE 
    1. Measure the voltage on the (K24) CKP Signal circuit at the CKP Sensor harness connector.

      Is the voltage between 4.8 and 5.2 volts?

      Yes 

      • Go To  8

      No 

      • Go To  10
  8. CHECK THE (K925) SENSOR GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance of the (K925) CKP Sensor Ground circuit between the CKP Sensor harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  9

      No 

      • Repair the (K925) CKP Sensor Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  9. VISUALLY INSPECT THE TARGET WHEEL/PULSE RING FOR DAMAGE OR EXCESSIVE RUNOUT 
    1. Disconnect the battery ground cable.
    2. Remove the CKP Sensor.
    3. Visually inspect the sensor mounting location for damage, foreign material.
    4. Rotate the engine and if possible inspect the Target Wheel for any signs of damage.
    5. Inspect the target wheel for any signs of damage by placing a bore scope into the CKP Sensor bore and manually rotate the engine slowly using a wrench on the crank damper bolt. For stamped steel targets, pay close attention to the light reflection of the bore scope light on each tooth. If a tooth is bent, the reflection (bright spot) will move in relation to the reflection of the other teeth that are not bent. The light reflection will remain in the same location on each tooth if none of the teeth are bent. For powder metal targets, look for any tooth that is dull or does not shine as compared to the other teeth. The rough surface that remains from a tooth that has broken off appears to be dull or non-reflective.

      Were any problems found?

      Yes 

      • Repair issues in the mounting location or repair or replace the Target Wheel / Pulse Ring as necessary. With the scan tool, perform "The Phonic Wheel Reset"  Procedure.
        NOTE:

        "The Phonic Wheel Reset" procedure must be performed every time there has been a repair or replacement made to a CMP Sensor, CKP sensor, flywheel, valvetrain, timing chain or gears. Failure to do so can cause a misfire fault to set.

      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Replace the Crank Position Sensor in accordance with the Service Information. With the scan tool, perform "The Phonic Wheel Reset"  Procedure.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
        NOTE:

        "The Phonic Wheel Reset" procedure must be performed every time there has been a repair or replacement made to a CMP Sensor, CKP sensor, flywheel, valvetrain, timing chain or gears. Failure to do so can cause a misfire fault to set.

      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  10. CHECK THE (K24) CKP SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Check for continuity between ground and the (K24) CKP Signal circuit at the CKP Sensor harness connector.

      Is there continuity between ground and the (K24) CKP Signal circuit?

      Yes 

      • Repair the (K24) CKP Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  11
  11. CHECK THE (K24) CKP SIGNAL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Measure the resistance of the (K24) CKP Signal circuit between the CKP Sensor harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  12

      No 

      • Repair the (K24) CKP Signal circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  12. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Perform any Service Bulletins that apply.
    2. Disconnect all PCM harness connectors.
    3. Disconnect all related in-line harness connections (if equipped).
    4. Disconnect the related component harness connectors.
    5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Check for spread terminals and verify proper terminal tension.

      Repair any conditions that are found.

    6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    9. With the scan tool, erase DTCs.
    10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    11. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

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