P050A
3UR-FE ENGINE CONTROL: SFI SYSTEM: P050A: Cold Start Idle Air Control System Performance
P050A - Cold Start Idle Air Control System Performance
DESCRIPTION
This monitor will run when the engine is started with the engine coolant temperature at -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 with the engine coolant temperature at below 50°C (122°F), the ECM (PCM) measures the accumulated mass air flow at engine idling. If it does not reach the criteria within 10 seconds, the ECM (PCM) 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 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 cable is disconnected from the negative (-) battery terminal during inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be stored with the ISC learning values cleared.
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 Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the Techstream on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation).
4. Turn the engine switch off and wait for at least 30 seconds.
5. Turn the engine switch on (IG) and turn the Techstream on [A].
6. Enter the following menu items: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
7. Check that "Coolant Temp" in the Data List are 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
- If a pending DTC is output, the system is malfunctioning.
- 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: P050A.
14. Check the DTC judgment result.
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].
15. If the 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. Freeze frame data records 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.
PROCEDURE
1. CHECK DTCS
OK:
Any other DTCs are not output.
NG -- GO TO DIAGNOSTIC TROUBLE CODE 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 engine switch on (IG) and turn the Techstream on.
(c) Enter the following menus: Powertrain / Engine and ECT / Data List / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.
(d) Read the values displayed on the Techstream.
(e) Add together the Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values to obtain the total fuel trim.
Result:
Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.
NG -- CHECK VVT SYSTEM
OK -- Continue to next step.
3. INSPECT THROTTLE BODY
(a) Check for deposits around the throttle valve and throttle valve condition.
OK:
No deposits around throttle valve and throttle valve moves smoothly.
OK -- REPLACE ECM
NG -- REPAIR OR REPLACE THROTTLE BODY
4. CHECK VVT SYSTEM
(a) Allow the engine to idle after the engine is warmed up.
(b) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
(c) Turn on Control the VVT System (Bank 1) or Control the VVT System (Bank 2) to advance the valve timing.
(d) Check the engine condition.
OK:
The engine stalls or idles roughly when Control the VVT System is ON (VVT system is OK).
NG -- CHECK AND REPAIR VVT SYSTEM
OK -- Continue to next step.
5. CHECK PCV SYSTEM
(a) Allow the engine to idle.
(b) Pinch the positive crankcase ventilation (PCV) hose.
(c) Check the engine speed.
OK:
The engine speed rises when the PCV hose is pinched.
NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.
6. 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
OK -- Continue to next step.
7. CHECK AIR INDUCTION SYSTEM
(a) Check the air induction system for vacuum leakage Intake System.
OK -- REPLACE MASS AIR FLOW METER
NG -- REPAIR OR REPLACE AIR INDUCTION SYSTEM
8. REPAIR OR REPLACE THROTTLE BODY
(a) Repair or replace the throttle body Removal.
NEXT -- CHECK DTCS
9. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- CHECK DTCS
10. CHECK AND REPAIR VVT SYSTEM
NEXT -- CHECK DTCS
11. REPAIR OR REPLACE PCV HOSE
NEXT -- CHECK DTCS
12. REPLACE AIR CLEANER FILTER
NEXT -- CHECK DTCS
13. REPAIR OR REPLACE AIR INDUCTION SYSTEM
NEXT -- CHECK DTCS
14. REPLACE MASS AIR FLOW METER
(a) Replace the mass air flow meter Removal.
NEXT -- Continue to next step.
15. CHECK DTCS
NOTICE:
In 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 engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs DTC Check / Clear.
(e) Turn the engine switch off.
(f) Turn the engine switch on (IG) and turn the Techstream on.
(g) Start the engine and warm it up.
(h) Refer to the confirmation driving pattern.
(i) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(j) Input the DTC: P050A.
(k) Check the DTC judgment result.
Result
NEXT -- END