Brand:

Toyota

Model Name:

4Runner GRN210 215 UZN210 215

Manual:

Repair Manual

Section:

1Gr-Fe Engine Control System

Title:

Sfi System

  1. Description

  2. Monitor description

  3. Monitor strategy

  4. Typical enabling conditions

  5. Typical malfunction thresholds

  6. Inspection procedure

  7. Check any other dtcs output (in addition to dtc p050a and/or p050b)

  8. Read value using intelligent tester (fuel trim)

  9. Check pcv hose connections

  10. Check air induction system

  11. Replace mass air flow meter

  12. Check whether dtc output recurs (dtc p050a and/or p050b)

  13. Repair or replace pcv hose

  14. Check whether dtc output recurs (dtc p050a and/or p050b)

  15. Repair or replace air induction system

  16. Check whether dtc output recurs (dtc p050a and/or p050b)

  17. Check throttle valve

  18. Replace ecm

  19. Check whether dtc output recurs (dtc p050a and/or p050b)

  20. Replace throttle body assembly

  21. Check whether dtc output recurs (p050a and/or p050b)

DTC P050A Cold Start Idle Air Control System Performance

DTC P050B Cold Start Ignition Timing Performance


​

DESCRIPTION

The Electronic Throttle Control System (ETCS) controls the engine idling speed. The ETCS operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idling speed.
In addition, the ECM retards the ignition timing and the ETCS increases the intake air amount to quickly increase the catalyst temperature at cold start to reduce emissions.

DTC No.
DTC Detection Conditions
Trouble Areas
P050A
Accumulated intake air amount during 10 seconds of idling after cold start, less than threshold (2 trip detection logic)
  1. Throttle body assembly
  2. Mass air flow meter
  3. Air induction system
  4. PCV hose connections
  5. Air cleaner filter element
  6. ECM
P050B
Ignition timing retard value insufficient for 5 seconds or more during 10 seconds of P050A monitoring duration at cold start (2 trip detection logic)
  1. Throttle body assembly
  2. Mass air flow meter
  3. Air induction system
  4. PCV hose connections
  5. Air cleaner filter element
  6. ECM

MONITOR DESCRIPTION


The engine coolant temperature is between -10°C (14°F) or more when the engine starts. 4Runner

The ECM monitors the intake air amount during idling and the ignition timing.
When the engine coolant temperature is between -10°C and 50 °C (14°F and 122°F), the ECM calculates the idling intake air amount for 10 seconds, beginning 3 seconds after the engine starts.
When the accumulated value is below the threshold, the ECM interprets this as a malfunction in the Idle Speed Control (ISC) system at cold start.
The ECM also monitors the ignition timing at cold start, and judges it to be incorrect when it is advanced to the same value for a warm engine for 5 seconds or more of the 10 second monitoring period.
Example:
P050A is detected when all conditions below are met (2 trip detection logic).
  1. The engine coolant temperature is between -10°C (14°F) or more when the engine starts.
  2. The engine idles for 3 seconds after engine start.
  3. The accumulated intake air amount is below the threshold.
It a malfunction is not repaired successfully, the ECM sets the DTC and illuminates the MIL 3 second after the engine is next started.
NOTICE:
When the negative battery terminal is disconnected during inspection or repairs, the ISC learning values are cleared. The ISC learning must be performed by warming up the engine and idling for 5 minutes with the ECT at 75°C (167°F) or more because DTCs cannot be detected with the ISC learning values cleared.

MONITOR STRATEGY


Related DTCs
P050A: Idle speed control problem at cold
P050B: Idle ignition timing problem at cold
Required Sensors/Components (Main)
Mass air flow meter
Required Sensors/Components (Related)
Engine Coolant Temperature (ECT) sensor, Throttle position sensor, Vehicle speed sensor
Frequency of Operation
Once per driving cycle
Duration
10 seconds
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


P050A:
Battery voltage
8 V or more
Time after engine start
3 seconds or more
Starter
OFF
ECT at engine start
-10°C (14°F) or more
ECT
-10°C to 50°C (14°F to 122°F)
Engine idling time
3 seconds or more
Fuel-cut
OFF
Vehicle speed
Less than 1.875 mph (3 km/h)
Time after shift position changed (A/T)
1 second or more

P050B:
Battery voltage
8 V or more
Time after engine start
3 seconds or more
Starter
OFF
ECT at engine start
-10°C (14°F) or more
ECT
-10°C to 50°C (14°F to 122°F)
Engine idling time
3 seconds or more
Fuel-cut
OFF
Vehicle speed
Less than 1.875 mph (3 km/h)

TYPICAL MALFUNCTION THRESHOLDS


P050A:
Accumulated air flow amount (A/T)
Varies with ECT (Example: Less than 42.5 g)

P050B:
Accumulated time when ignition timing retard is cut off
5 seconds or more

INSPECTION PROCEDURE

HINT:
Read freeze frame data using an intelligent tester. Freeze frame data record the engine condition when malfunctions are detected. 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 P050A AND/OR P050B)

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester ON.

  1. Select the following the menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read the DTCs.

    Result:

    Display (DTC Output)
    		Proceed to
    P050A and/or P050B
    		A
    P050A and/or P050B and other DTCs
    		B
    HINT:
    If any DTCs other than P050A and P050B are output, troubleshoot those DTCs first.


Bnext
GO TO DTC CHART
A
next down

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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / SHORT FT #1 and LONG FT #1.

  1. Read the values displayed on the tester.

  1. Add together the SHORT FT #1 and LONG FT #1 values to obtain the total FUEL TRIM.

    OK:
    Total of SHORT FT #1 and LONG FT #1 values is between -20 % and 20 %.


OKnext
Go to step 11
NG
next down

3.CHECK PCV HOSE CONNECTIONS
OK:
PCV hose is connected correctly and is not damaged.


NGnext
Go to step 7
OK
next down

4.CHECK AIR INDUCTION SYSTEM

  1. Check the air induction system for vacuum leakage.

    OK:
    No leakage from air induction system.


NGnext
Go to step 9
OK
next down

5.REPLACE MASS AIR FLOW METER

  1. Replace the mass air flow meter.


NEXT
next down

6.CHECK WHETHER DTC OUTPUT RECURS (DTC P050A AND/OR P050B)
NOTICE:
In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the intelligent tester to the DLC.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Clear DTCs (Click here).

  1. Switch the ECM from normal mode to check mode on the tester.

  1. Start the engine to idle for a minute.

    OK:
    Stable fast idling.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    OK:
    No DTCs output.

NEXT
next down
END

7.REPAIR OR REPLACE PCV HOSE

NEXT
next down

8.CHECK WHETHER DTC OUTPUT RECURS (DTC P050A AND/OR P050B)
NOTICE:
In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the intelligent tester to the DLC.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Clear DTCs (Click here).

  1. Switch the ECM from normal mode to check mode on the tester.

  1. Start the engine to idle for a minute.

    OK:
    Stable fast idling.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    OK:
    No DTCs output.

NEXT
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END

9.REPAIR OR REPLACE AIR INDUCTION SYSTEM

NEXT
next down

10.CHECK WHETHER DTC OUTPUT RECURS (DTC P050A AND/OR P050B)
NOTICE:
In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the intelligent tester to the DLC.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Clear DTCs (Click here).

  1. Switch the ECM from normal mode to check mode on the tester.

  1. Start the engine to idle for a minute.

    OK:
    Stable fast idling.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    OK:
    No DTCs output.

NEXT
next down
END

11.CHECK THROTTLE VALVE

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

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


NGnext
Go to step 14
OK
next down

12.REPLACE ECM

  1. Replace the ECM (Click here).


NEXT
next down

13.CHECK WHETHER DTC OUTPUT RECURS (DTC P050A AND/OR P050B)
NOTICE:
In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the intelligent tester to the DLC.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Clear DTCs (Click here).

  1. Switch the ECM from normal mode to check mode on the tester.

  1. Start the engine to idle for a minute.

    OK:
    Stable fast idling.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    OK:
    No DTCs output.

NEXT
next down
END

14.REPLACE THROTTLE BODY ASSEMBLY

  1. Replace the throttle body assembly (Click here).


NEXT
next down

15.CHECK WHETHER DTC OUTPUT RECURS (P050A AND/OR P050B)
NOTICE:
In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

  1. Connect the intelligent tester to the DLC.

  1. Turn the ignition switch on.

  1. Turn the tester on.

  1. Clear DTCs (Click here).

  1. Switch the ECM from normal mode to check mode on the tester.

  1. Start the engine to idle for a minute.

    OK:
    Stable fast idling.

  1. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

  1. Read DTCs.

    OK:
    No DTCs output.

NEXT
next down
END