Dtc P050B Cold Start Ignition Timing Performance

Engine Hybrid System. Corolla. Zre142 Aze141
2Az-Fe Engine Control. Corolla. Zre142 Aze141

DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B)

READ VALUE USING TECHSTREAM (FUEL TRIM)

INSPECT THROTTLE BODY

REPAIR OR REPLACE THROTTLE BODY

CHECK PCV SYSTEM

CHECK INTAKE SYSTEM

CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT LINEAR)

READ VALUE USING TECHSTREAM (MAF)

REPAIR OR REPLACE PCV HOSE

REPAIR OR REPLACE INTAKE SYSTEM

REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

CHECK AND REPAIR VVT SYSTEM

CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION)

CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

REPLACE MASS AIR FLOW METER

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

DTC P050B Cold Start Ignition Timing Performance


DESCRIPTION

This monitor will run when the engine is started at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC is stored after the engine idles for 13 seconds (2 trip detection logic).
The DTC is designed to monitor the ignition timing at cold start. When the engine is started at an engine coolant temperature of below 50°C (122°F), the ECM checks the ignition timing during engine idling. If the ignition timing advances beyond the specified level within 10 seconds, the ECM interprets this as a malfunction. The MIL is illuminated and a DTC is stored when the malfunction is detected in consecutive driving cycles (2 trip detection logic).
NOTICE:
When the cable is disconnected from the negative (-) battery terminal during inspections or repairs, the idle speed control learned values are cleared. This DTC cannot be stored with the idle speed control learned values cleared.
HINT:
The idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.

Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P050B Cold Start Ignition Timing Performance


DTC No.
DTC Detection Condition
Trouble Area
P050B
Insufficient ignition timing retard at cold start (2 trip detection logic).
  1. Throttle body
  2. Mass air flow meter
  3. PCV system
  4. Air cleaner filter element
  5. Intake system
  6. VVT system
  7. Wire harness or connector
  8. ECM

MONITOR STRATEGY


Related DTCs
P050B: Cold Start Ignition Timing Performance
Required Sensors/Components (Main)
Throttle body
Required Sensors/Components (Related)
Mass air flow meter
Engine coolant temperature sensor
Frequency of Operation
Once per driving cycle
Duration
10 seconds
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


Monitor runs whenever following DTCs not stored
P0010 (VVT Oil Control Valve)
P0011 (VVT System - Advance)
P0012 (VVT System - Retard)
P0016 (VVT System - Misalignment)
P0102, P0103 (Mass Air Flow Meter)
P0115, P0117, P0118 (Engine Coolant Temperature Sensor)
P0120, P0121 P0122, P0123, P0220, P0222, P0223, P2135 (Throttle Position Sensor)
P0125 (Insufficient Engine Coolant Temperature for Closed Loop Fuel Control)
P014C, P014D, P015A, P015B, P2195, P2196, P2237, P2238, P2239, P2252, P2253 (Air Fuel Ratio Sensor - Sensor 1)
P0171, P0172 (Fuel System)
P0301, P0302, P0303, P0304 (Misfire)
P0335 (Crankshaft Position Sensor)
P0340 (Camshaft Position Sensor)
P0351, P0352, P0353, P0354 (Igniter)
P0500 (Vehicle Speed Sensor)
Battery voltage
8 V or more
Time after engine start
3 seconds or more
Starter
Off
Engine coolant temperature at engine start
-10°C (14°F) or more
Engine coolant temperature
-10 to 50°C (14 to 122°F)
Fuel-cut
Off
Engine idling time
3 seconds or more
Vehicle speed
Less than 1.875 mph (3 km/h)
Atmospheric pressure
76 kPa(abs) [570 mmHg(abs)] or higher

TYPICAL MALFUNCTION THRESHOLDS


Accumulated time when ignition timing retard value is cut off
5 seconds or more

CONFIRMATION DRIVING PATTERN

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on [A].
  6. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
  7. Check that "Coolant Temp" in the Data List is within the range of -10 to 50°C (14 to 122°F).
  8. Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the freeze frame data.
  9. Idle the engine for 1 minute or more [B].
  10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].
  11. Read the pending DTCs.
    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  12. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  13. Input the DTC: P050B.
  14. Check the DTC judgment result.

    Techstream Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    N/A
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, idle the engine for 3 minutes, let the engine cool down, and then perform steps [A] through [C] again.
  15. If no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).
    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0102 (Link).

INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
  1. DTC P050B may be output when the engine has the symptoms listed below. If necessary, check the trouble areas listed below.

    Symptom
    		Factor
    		Trouble Area
    Low idle speed when engine is cold (immediately after engine start)
    		Excessive engine friction
    1. Engine oil deterioration
    2. Drive belt tension
    3. A/C compressor
    4. Generator
    Rough idle when engine is cold (immediately after engine start)
    		Abnormal combustion
    		Fuel quality
  2. Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050B)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

  1. Read the DTCs.

    Result:

    Result
    		Proceed to
    P050B
    		A
    P050B and other DTCs
    		B
    HINT:
    If any DTCs other than P050B are output, troubleshoot those DTCs first.


B
GO TO DTC CHART (COROLLA_ZRE142 RM000000PDF0G9X.html)
A


2.READ VALUE USING TECHSTREAM (FUEL TRIM)
HINT:
Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.

  1. Connect the Techstream to the DLC3.

  1. Start the engine.

  1. Turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Gas AF Control / Short FT #1 or Long FT #1.

  1. Read the values displayed on the Techstream with the engine at idle.

  1. Add together the Short FT #1 or Long FT #1 values to obtain the total fuel trim.

    OK:
    Total of Short FT #1 or Long FT #1 values is between -20% and 20%.


NG
Go to step 5
OK


3.INSPECT THROTTLE BODY

  1. Check for deposits around the throttle valve and throttle valve condition.

    OK:
    No deposits around throttle valve and throttle valve moves smoothly.

    Result:

    Result
    		Proceed to
    NG
    		A
    OK
    		B


B
Go to step 14
A


4.REPAIR OR REPLACE THROTTLE BODY

  1. Repair or replace the throttle body (COROLLA_ZRE142 RM0000017UC03CX.html).



NEXT
Go to step 14

5.CHECK PCV SYSTEM

  1. Check the PCV hose connections.

OK:
PCV hose is connected correctly and is not damaged.


NG
Go to step 10
OK


6.CHECK INTAKE SYSTEM

  1. Check the intake system for vacuum leaks (COROLLA_ZRE142 RM00000341100ZX.html).

    OK:
    No leakage from intake system.


NG
Go to step 11
OK


7.CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

  1. Visually check that the air cleaner filter element is not excessively contaminated with dirt or oil.

    OK:
    Air cleaner filter element is not excessively contaminated with dirt or oil.


NG
Go to step 12
OK


8.PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT LINEAR)

  1. Operate the VVT system through the Active Test, and check if the VVT system is operating normally.

    1. Perform the Active Test, referring to DTC P0011 Inspection Procedure (COROLLA_ZRE142 RM000000PDU0PSX_09_0002.html).



NG
Go to step 13
OK


9.READ VALUE USING TECHSTREAM (MAF)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / MAF, Coolant Temp and Engine Speed.

  1. Allow the engine to idle until Coolant Temp reaches 75°C (167°C) or higher.

  1. Read MAF with the engine speed at 3000 rpm.

    Standard Value:
    Between 7.6 gm/s and 11.4 gm/s (Shift lever: Neutral, A/C: off)


OK
Go to step 14

NG
Go to step 15

10.REPAIR OR REPLACE PCV HOSE

  1. Repair or replace the PCV hose.



NEXT
Go to step 14

11.REPAIR OR REPLACE INTAKE SYSTEM

  1. Repair or replace the intake system.



NEXT
Go to step 14

12.REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

  1. Replace the air cleaner filter element sub-assembly.



NEXT
Go to step 14

13.CHECK AND REPAIR VVT SYSTEM

  1. Check and repair the VVT system.

    HINT:
    1. Refer to DTC P0011 Inspection Procedure (COROLLA_ZRE142 RM000000PDU0PSX_08.html).

NEXT


14.CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear the DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).

  1. Turn the ignition switch off and wait for at least 30 seconds.

  1. Turn the ignition switch to ON and turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.

  1. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F)

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

  1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  1. Input the DTC: P050B.

  1. Check the DTC judgment result.

    Result:

    Result
    		Proceed to
    NORMAL (No output)
    		A
    ABNORMAL (P050B)
    		B


B
Go to step 15
A

END

15.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION)

  1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM (COROLLA_ZRE142 RM000000UZ30C8X.html).

    HINT:
    Repair any problems.

NEXT


16.CHECK WHETHER DTC OUTPUT RECURS (DTC P050B)
NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear the DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).

  1. Turn the ignition switch off and wait for at least 30 seconds.

  1. Turn the ignition switch to ON and turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.

  1. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F)

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

  1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  1. Input the DTC: P050B.

  1. Check the DTC judgment result.

    Result:

    Result
    		Proceed to
    ABNORMAL (P050B)
    		A
    NORMAL (No output)
    		B


B
END
A


17.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

  1. Disconnect the mass air flow meter connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):

    Tester Connection
    		Condition
    		Specified Condition
    B2-5 (VG) - B31-118 (VG)
    		Always
    		Below 1 Ω
    B2-4 (E2G) - B31-116 (E2G)

    Standard Resistance (Check for Short):

    Tester Connection
    		Condition
    		Specified Condition
    B2-5 (VG) or B31-118 (VG) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the mass air flow meter connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)
OK


18.REPLACE MASS AIR FLOW METER

  1. Replace the mass air flow meter (COROLLA_ZRE142 RM0000017TX03AX.html).

    HINT:
    If the result of the inspection performed in step 9 indicated no problem, proceed to the next step without replacing the mass air flow meter.

NEXT


19.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear the DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).

  1. Turn the ignition switch off and wait for at least 30 seconds.

  1. Turn the ignition switch to ON and turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.

  1. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).

  1. Start the engine and warm it up.

  1. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

  1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  1. Input the DTC: P050B.

  1. Check the DTC judgment result.

    Result:

    Result
    		Proceed to
    NORMAL (No output)
    		A
    ABNORMAL (P050B)
    		B


B
REPLACE ECM (COROLLA_ZRE142 RM000002WT402ZX.html)
A

END