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Home >> Honda >> 2018 >> Fit EX-L >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostics (P0455-P16F6) >> DTC Troubleshooting >> DTC P050B: Cold Start Ignition Timing Control System Performance Problem
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DTC P050B: Cold Start Ignition Timing Control System Performance Problem

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to: HOW TO TROUBLESHOOT THE FUEL AND EMISSIONS SYSTEMS or How to Troubleshoot the CVT System(CVT) .

DTC Description Confirmed DTC Pending DTC Freeze Frame
P050B Cold Start Ignition Timing Control System Performance Problem      

DTC (PGM-FI)

  1. PGM-FI system check:

    - 1. Turn the vehicle to the ON mode.

    - 2. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC Freeze Frame
           

    Are any Pending or Confirmed DTCs other than P050B indicated?

    YES 

    Go to the indicated DTC's troubleshooting.

    NO 

    Go to step 2.

  2. Intake air duct visual check:

    - 1. Check for a poor connection or blockage at the intake air duct.

    Is it OK?

    YES 

    Go to step 3.

    NO 

    Reconnect or repair the intake air duct.

  3. Air cleaner housing visual check:

    - 1. Check for a poor connection or blockage at the air cleaner housing.

    Is it OK?

    YES 

    Go to step 4.

    NO 

    Replace the air cleaner housing .

  4. Air cleaner element visual check:

    - 1. Check for dirt or debris on the air cleaner element.

    Is it dirty?

    YES 

    Replace the air cleaner element .

    NO 

    Go to step 5.

  5. Problem verification:

    - 1. Let the engine cool until the value of ECT SENSOR 1 is 122 °F (50 °C) or less.

    Signal Current conditions
    Values Unit
    ECT SENSOR 1    

    - 2. Clear the DTC with the HDS.

    - 3. Start the engine, and let it idle for 10 seconds or more.

    - 4. Monitor the OBD STATUS for DTC P050B in the DTCs MENU with the HDS.

    DTC Description OBD STATUS
    P050B Cold Start Ignition Timing Control System Performance Problem  

    Does the HDS indicate FAILED?

    YES 

    The failure is duplicated. Go to step 6.

    NO 

    If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the CKP sensor, the throttle body, MAF sensor/IAT sensor 1, ECT sensor 1, ECT sensor 2, and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 5-1 and recheck.

  6. Determine possible failure area (CKP sensor, others):

    - 1. Check the ignition timing .

    Is the ignition timing OK?

    YES 

    Go to step 8.  8

    NO 

    Go to step 7.

  7. CKP sensor and CKP pulse plate visual check:

    - 1. Check for damage at the CKP sensor and the CKP pulse plate.

    Is the CKP sensor and CKP pulse plate damaged?

    YES 

    Replace the CKP sensor and/or the CKP pulse plate .

    NO 

    The CKP sensor and the CKP pulse plate are OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P050B goes away and the PCM was updated, troubleshooting is complete. If DTC P050B goes away and the PCM was substituted, replace the original PCM .

  8. Throttle body test:

    - 1. Select the ETCS TEST in the INSPECTION MENU with the HDS.

    ETCS TEST

    Is the THROTTLE ACTUATOR CONTROL VALVE normal?

    YES 

    Go to step 9.

    NO 

    Replace the throttle body .

  9. MAF sensor performance check:

    - 1. Start the engine.

    - 2. Hold the engine speed at 3, 000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.

    - 3. While holding the engine speed at 2, 500 rpm for 30 seconds, check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    MAF SENSOR 3.8-5.4 (M/T) / 3.9-5.5 (CVT) g/s    

    Do the current condition(s) match the threshold?

    YES 

    The MAF sensor is OK. Go to step 10.

    NO 

    Replace MAF sensor/IAT sensor 1 .

  10. ECT sensor 1 and ECT sensor 2 performance check:

    - 1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Allow the engine to cool to ambient temperature.

    - 3. Note the ambient temperature.

    - 4. Turn the vehicle to the ON mode.

    - 5. Quickly note the value of the ECT SENSOR 1 and ECT SENSOR 2 in the DATA LIST with the HDS.

    Signal Current conditions
    Values Unit
    ECT SENSOR 1    
    ECT SENSOR 2    

    - 6. Compare the value of ECT SENSOR 1 and the value of ECT SENSOR 2 with the ambient temperature individually.

    Does either sensor differ more than 5.4 °F (3 °C) from the ambient temperature?

    YES 

    Replace the sensor that differed more than 5.4 °F (3 °C) from the ambient temperature.

    NO 

    The ECT sensors are OK. Check and repair any problems with the following items. Repair or replace them if needed. If every item is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P050B goes away and the PCM was updated, troubleshooting is complete. If DTC P050B goes away and the PCM was substituted, replace the original PCM .

    • Engine compression and cylinder leakdown
    • Valve pause system
    • Engine oil
    • A/C system