Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001HT3Z
Model Year Start: 2020 Model: Corolla Prod Date Range: [03/2019 - 11/2022]
Title: 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P050A; Cold Start Idle Air Control System Performance; 2020 - 2023 MY Corolla [03/2019 - 11/2022]

DTC

P050A

Cold Start Idle Air Control System Performance

MONITOR 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 will be stored after the engine idles for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the idle air control at cold start. When the engine is started at an engine coolant temperature of less than 50°C (122°F), the ECM measures the accumulated mass air flow during engine idling. If the accumulated mass air flow does not reach 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).

The electronic throttle control system controls the idle speed. The electronic throttle control system operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idle speed.

NOTICE:

The idle speed control learned values are cleared by performing a learned value reset. Idle speed control learning needs to be performed before this DTC can be stored.

HINT:

Idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

Note

P050A

Cold Start Idle Air Control System Performance

Insufficient mass air flow after a cold start (2 trip detection logic).

  • Throttle body assembly
  • Mass air flow meter sub-assembly
  • PCV system
  • Air cleaner filter element sub-assembly
  • Intake system
  • VVT system
  • Wire harness or connector
  • ECM

Comes on

DTC stored

DTC for Mexico Models

- Does not apply

MONITOR STRATEGY

Related DTCs

P050A: Cold start idle air speed control system

Required Sensors/Components (Main)

Throttle body assembly

Required Sensors/Components (Related)

Engine coolant temperature sensor

Mass air flow meter sub-assembly

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 the following DTCs are not stored

P0010 (Camshaft timing oil control valve)

P0011 (VVT system - advance)

P0012 (VVT system - retard)

P0013 (Exhaust camshaft timing oil control valve)

P0014 (Exhaust VVT system - advance)

P0015 (Exhaust VVT system - retard)

P0016 (VVT system - misalignment)

P0017 (Exhaust VVT system - misalignment)

P0102, P0103 (Mass air flow meter)

P0107, P0108 (Manifold absolute pressure)

P0115, P0117, P0118 (Engine coolant temperature sensor)

P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135 (Throttle position sensor)

P0125 (Insufficient coolant temperature for closed loop fuel control)

P014C, P014D, P015A, P015B, P2195, P2196, P2237, P2238, P2239, P2252, P2253 (Air fuel ratio sensor)

P0171, P0172 (Fuel system)

P0300, P0301, P0302, P0303, P0304 (Misfire)

P0335 (Crank position sensor)

P0340, P0342, P0343 (Cam position sensor)

P0365, P0367, P0368 (Exhaust cam position sensor)

P0500 (Vehicle speed sensor)

P219A, P219C, P219D, P219E, P219F (Air-fuel ratio imbalance)

Battery voltage

8 V or higher

Time after engine start

3 seconds or more

Starter

Off

Engine coolant temperature at engine start

-10°C (14°F) or higher

Engine coolant temperature

-10°C (14°F) or higher, and less than 50°C (122°F)

Engine idling time

3 seconds or more

Fuel-cut

Off

Vehicle speed

Less than 3 km/h (1.875 mph)

Time after shift position changed

1 second or more (for CVT models)

Atmospheric pressure

76 kPa(abs) [11 psi(abs)] or higher

TYPICAL MALFUNCTION THRESHOLDS

Accumulated mass air flow

  • Shift lever in N: Less than 30.625 g (varies with engine coolant temperature and engine coolant temperature at engine start) (for CVT models)
  • Shift lever in D: Less than 30 g (varies with engine coolant temperature and engine coolant temperature at engine start) (for CVT models)
  • Less than 29.375 g (varies with engine coolant temperature and engine coolant temperature at engine start) (for Manual Transaxle models)

CONFIRMATION DRIVING PATTERN

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON.
  3. Turn the Techstream on.
  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  5. Turn the ignition switch off and wait for at least 30 seconds.
  6. Turn the ignition switch to ON [A].
  7. Turn the Techstream on.
  8. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
  9. Check that "Coolant Temp" in the Data List is within the range of -10 to 50°C (14 to 122°F).
  10. Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the Freeze Frame Data.
  11. Idle the engine for 1 minute or more [B].
  12. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].
  13. Read the pending DTC.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
  14. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  15. Input the DTC: P050A.
  16. Check the DTC judgment result.

    Techstream Display

    Description

    NORMAL

    • DTC judgment completed
    • System normal

    ABNORMAL

    • DTC judgment completed
    • System abnormal

    INCOMPLETE

    • DTC judgment not completed
    • Perform driving pattern after confirming DTC enabling conditions

    N/A

    • Unable to perform DTC judgment
    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • 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.
  17. If no pending DTC is output, perform a universal trip and check for permanent DTCs.

    Click here 2020 - 2022 MY Corolla [03/2019 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

    HINT:

    • If a permanent DTC is output, the system is malfunctioning.
    • If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0102.

Click here 2020 - 2023 MY Corolla [03/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P0102,P0103; Mass Air Flow Circuit Low+

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1.

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(e) Read the DTCs.

Powertrain > Engine and ECT > Trouble Codes

Result

Proceed to

DTC P050A is output

A

DTC P050A and other DTCs are output

B

HINT:

If any DTCs other than P050A are output, troubleshoot those DTCs first.

B

GO TO DTC CHART 2020 MY Corolla [03/2019 - 04/2020]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: DIAGNOSTIC TROUBLE CODE CHART 2021 - 2022 MY Corolla [04/2020 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: DIAGNOSTIC TROUBLE CODE CHART 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: DIAGNOSTIC TROUBLE CODE CHART

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 sub-assembly.

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Short FT B1S1, Long FT B1S1.

Powertrain > Engine and ECT > Data List

Tester Display

Short FT B1S1

Long FT B1S1

(e) Read the values displayed on the Techstream at engine idle.

(f) Add the Short FT B1S1 and Long FT B1S1 values to obtain the total fuel trim.

Standard:

Techstream Display

Specified Condition

Total of Short FT B1S1 and Long FT B1S1

Between -20 and 20%

NG

GO TO STEP 5

OK

3.

INSPECT THROTTLE BODY ASSEMBLY (VISUALLY CHECK THROTTLE VALVE)

(a) Check for foreign matter between the throttle valve and housing. If necessary, clean the throttle body assembly. Also, check that the throttle valve moves smoothly.

OK:

No deposits around the throttle valve and throttle valve moves smoothly.

OK

GO TO STEP 10

NG

4.

REPLACE THROTTLE BODY ASSEMBLY

(a) Replace the throttle body assembly.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): THROTTLE BODY: REMOVAL

HINT:

Perform "Inspection After Repair" after replacing the throttle body assembly.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: INITIALIZATION

NEXT

GO TO STEP 16

5.

CHECK PCV SYSTEM

(a) Check the PCV hose connections.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (EMISSION CONTROL): PCV VALVE: COMPONENTS

OK:

PCV valve and hose are connected correctly and are not damaged.

NG

GO TO STEP 15

OK

6.

CHECK INTAKE SYSTEM

(a) Check the intake system for vacuum leaks.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (INTAKE / EXHAUST): INTAKE SYSTEM: ON-VEHICLE INSPECTION

OK:

No leaks from intake system.

NG

GO TO STEP 14

OK

7.

CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

(a) Visually check that the air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

OK:

The air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

NG

GO TO STEP 13

OK

8.

PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE VVT LINEAR)

(a) 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 Procedure (VVT system for intake camshaft).

Click here 2020 - 2023 MY Corolla [03/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P0011,P0012; Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 1)+

(2) Perform the Active Test, referring to DTC P0014 Procedure (VVT system for exhaust camshaft).

Click here 2020 - 2023 MY Corolla [03/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P0014,P0015; Camshaft Position "B" - Timing Over-Advanced or System Performance (Bank 1)+

NG

GO TO STEP 12

OK

9.

READ VALUE USING TECHSTREAM (MAF)

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Engine Speed, MAF and Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display

Engine Speed

MAF

Coolant Temp

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

(f) Read MAF with the engine speed at 3000 rpm.

Standard:

Techstream Display

Condition

Specified Condition

MAF

  • Engine warmed up
  • Shift lever position: N (neutral)
  • A/C: Off
  • Engine Speed: 3000 rpm

Between 5.0 and 10.0 gm/sec

NG

GO TO STEP 18

OK

10.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

(e) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

11.

CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

NOTICE:

In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the Freeze Frame Data).

(a) Turn the ignition switch to ON.

(b) Turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display

Coolant Temp

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

(e) Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.

(f) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Powertrain > Engine and ECT > Utility

Tester Display

All Readiness

(h) Input the DTC: P050A.

(i) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

A

ABNORMAL

(DTC P050A is output)

B

A

CHECK FOR INTERMITTENT PROBLEMS

B

GO TO STEP 18

12.

CHECK AND REPAIR VVT SYSTEM

(a) Check and repair the VVT system.

HINT:

  • Refer to DTC P0011 Procedure (VVT system for intake camshaft).

    Click here 2020 - 2023 MY Corolla [03/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P0011,P0012; Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 1)

  • Refer to DTC P0014 Procedure (VVT system for exhaust camshaft).

    Click here 2020 - 2023 MY Corolla [03/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: P0014,P0015; Camshaft Position "B" - Timing Over-Advanced or System Performance (Bank 1)

NEXT

GO TO STEP 16

13.

REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

(a) Replace the air cleaner filter element sub-assembly.

NEXT

GO TO STEP 16

14.

REPAIR OR REPLACE INTAKE SYSTEM

(a) Repair or replace the intake system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the intake system.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: INITIALIZATION

NEXT

GO TO STEP 16

15.

REPAIR OR REPLACE PCV HOSE

(a) Repair or replace PCV valve or hose.

NEXT

16.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

(e) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

17.

CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

NOTICE:

In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the Freeze Frame Data).

(a) Turn the ignition switch to ON.

(b) Turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display

Coolant Temp

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

(e) Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.

(f) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Powertrain > Engine and ECT > Utility

Tester Display

All Readiness

(h) Input the DTC: P050A.

(i) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

A

ABNORMAL

(DTC P050A is output)

B

A

END

B

18.

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY CONNECTOR CONNECTION)

(a) Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: ELECTRONIC CIRCUIT INSPECTION PROCEDURE

HINT:

Repair any problems.

NEXT

19.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

(e) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

20.

CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

NOTICE:

In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the Freeze Frame Data).

(a) Turn the ignition switch to ON.

(b) Turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display

Coolant Temp

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

(e) Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.

(f) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Powertrain > Engine and ECT > Utility

Tester Display

All Readiness

(h) Input the DTC: P050A.

(i) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

A

ABNORMAL

(DTC P050A is output)

B

A

END

B

21.

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

(a) Disconnect the mass air flow meter sub-assembly connector.

(b) Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

C26-1 (FG) - C77-137 (VG)

Always

Below 1 Ω

C26-2 (E2G) - C77-104 (E2G)

Always

Below 1 Ω

C26-3 (VCC) - C77-103 (VCVG)

Always

Below 1 Ω

C26-1 (FG) or C77-137 (VG) - Body ground and other terminals

Always

10 kΩ or higher

C26-3 (VCC) or C77-103 (VCVG) - Body ground and other terminals

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

22.

REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

(a) Replace the mass air flow meter sub-assembly.

Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): MASS AIR FLOW METER: REMOVAL

HINT:

  • If the result of the inspection performed in step 9 (READ VALUE USING TECHSTREAM (MAF)) indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly.
  • Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

    Click here 2020 - 2023 MY Corolla [01/2019 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): SFI SYSTEM: INITIALIZATION

NEXT

23.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

(e) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

24.

CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

NOTICE:

In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the Freeze Frame Data).

(a) Turn the ignition switch to ON.

(b) Turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

Powertrain > Engine and ECT > Data List

Tester Display

Coolant Temp

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

(e) Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.

(f) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Powertrain > Engine and ECT > Utility

Tester Display

All Readiness

(h) Input the DTC: P050A.

(i) Check the DTC judgment result.

Result

Proceed to

NORMAL

(DTCs are not output)

A

ABNORMAL

(DTC P050A is output)

B

A

END

B

REPLACE ECM 2020 - 2022 MY Corolla [03/2019 - 09/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL 2023 MY Corolla [09/2022 - 11/2022]; 2ZR-FAE (ENGINE CONTROL): ECM: REMOVAL