P050A

2AZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P050A: Cold Start Idle Air Control System Performance
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 set 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 lower than 50°C (122°F), the ECM measures the accumulated mass air flow at engine idling. If it does not reach the specified level within 10 seconds, the ECM interprets this as a malfunction. The MIL is illuminated and a DTC is set when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

The ETCS (Electronic Throttle Control System) controls the idle speed. The ETCS operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idle speed.

NOTICE:
When the negative battery terminal is disconnected during inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be set with the ISC learning values cleared.

HINT
The ISC learning is performed when the engine is warmed up and has been idling for 5 minutes.









MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

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

3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation) [A].

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

5. Check that "Coolant Temp" in the Data List are within the range of -10 to 50°C.

6. Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the freeze frame data.

7. Idle the engine for 1 minute or more [B].

8. Enter the following menus: Powertrain / Engine and ECT / Trouble Code / Pending.

9. Read Pending DTCs [C].

HINT
If a pending DTC is output, the system is malfunctioning.

10. If a pending DTC is not output, enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

11. Input the DTC: P050A.

12. Check the DTC judgment result [C].





HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or UNKNOWN, idle the engine for 3 minutes, let the engine cool down, and then perform steps [A] through [C].

13. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.

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

INSPECTION 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) Select the following menu items: Powertrain / Engine and ECT / Trouble Codes.

(e) Read DTCs.

Result

Result:

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

NG -- GO TO DTC CHART Engine Control System - SFI System
OK -- Continue to next step.

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.

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream ON.

(d) Select the following menu items: Powertrain / Engine and ECT / Data List / A/F Control System / Short FT #1 and Long FT #1.

(e) Read the values displayed on the Techstream.

(f) 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%.

NG -- PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)
OK -- Continue to next step.

3. INSPECT THROTTLE BODY

(a) Check that there are no deposits around the throttle valve.

OK:

No deposits around the throttle valve.

NG -- REPAIR OR REPLACE THROTTLE BODY
OK -- Continue to next step.

4. REPLACE ECM

(a) Replace ECM Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

5. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream ON.

(d) Warm up the engine.

(e) Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1).

(f) Check the engine speed while operating the Oil Control Valve (OCV) using the Techstream.

OK:





NG -- CHECK AND REPAIR VVT SYSTEM
OK -- Continue to next step.

6. CHECK PCV SYSTEM

(a) Start the engine.

(b) Pinch the positive crankcase ventilation (PCV) hose.

(c) Check the engine rpm.

OK:

The engine rpm rises when the PCV hose is pinched.

NG -- REPAIR OR REPLACE PCV SYSTEM
OK -- Continue to next step.

7. CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

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

OK:

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

NG -- REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
OK -- Continue to next step.

8. CHECK AIR INDUCTION SYSTEM

(a) Check the air induction system for vacuum leaks Intake System.

OK:

No leak from the air induction system.

NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK -- Continue to next step.

9. REPLACE MASS AIR FLOW METER

(a) Replace mass air flow meter Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

10. REPAIR OR REPLACE THROTTLE BODY

(a) Repair or replace throttle body Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

11. CHECK AND REPAIR VVT SYSTEM

HINT
Refer to DTC P011 Inspection Procedure P0011

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

12. REPAIR OR REPLACE PCV SYSTEM

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

13. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

14. REPAIR OR REPLACE AIR INDUCTION SYSTEM

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

15. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)

NOTICE:
For this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream ON.

(d) Clear DTCs DTC Check / Clear.

(e) Switch the ECM from normal mode to check mode using the Techstream Scan Tool Testing and Procedures.

(f) Start the engine and idle it for one minute.

OK:

Stable fast idle

(g) Read DTCs.

OK:

No DTC is output.

NEXT -- END