P050A

1UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P050A: Cold Start Idle Air Control System Performance

DTC P050A - Cold Start Idle Air Control System Performance

DESCRIPTION

This monitor will run when the engine is started at -10 to 60°C (14 to 140°F) of the engine coolant temperature. The DTC will set after the engine idling 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 lower than 60°C (140°F) of the engine coolant temperature, the ECM measures the accumulated mass air flow at the engine idling. If it does not reach the criteria 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 (Electrical 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.
NOTE:
When the cable is disconnected from the negative (-) battery terminal during inspection or repairs, the ISC (Idle Speed Control) learned values are cleared. ISC learning needs to be performed before this DTC can be stored. To perform ISC learning, the engine must be warmed up by allowing it to idle for 5 minutes. For ISC learning to be successful, when the engine is started to warm it up, there must be at least 10 seconds of idling with the coolant temperature of below 30°C before allowing it to continue running for the 5 minute learning period.





MONITOR DESCRIPTION





MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





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 engine switch on (IG).
(c) Turn the Techstream ON.
(d) Select the following the menu items: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Result:





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

B -- GO TO DTC CHART
A -- 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) Start the engine.
(c) Turn the Techstream ON.
(d) Select the following menu items: Powertrain / Engine / Data List / A/F Control System / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.
(e) Read the values displayed on the Techstream at engine idle.
(f) 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.
OK:
Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.
Result:






B -- CHECK THROTTLE BODY ASSEMBLY
A -- Continue to next step.

3. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine and warm it up.
(d) Enter the following menus: Powertrain / Engine / Active Test / Control the VVT-iE Linear (Bank 1) or Control the VVT-iE Linear (Bank 2) / VVT-iE Aim Angle (Bank 1) and VVT-iE Change Angle (Bank 1) or VVT-iE Aim Angle (Bank 2) and VVT-iE Change Angle (Bank 2).
(e) Perform the Active Test operation with the engine speed at 1500 rpm.
OK:






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

4. CHECK PCV HOSE CONNECTIONS
OK:
PCV hose is connected correctly and is not damaged.
NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.

5. CHECK INTAKE SYSTEM
(a) Check the intake system for vacuum leakage.
OK:
No leakage from intake system.
NG -- REPAIR OR REPLACE INTAKE SYSTEM
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:
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.

7. REPLACE MASS AIR FLOW METER
(a) Replace the mass air flow meter Components.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
8. CHECK AND REPAIR VVT SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
9. REPAIR OR REPLACE PCV HOSE
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
10. REPAIR OR REPLACE INTAKE SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
11. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
12. CHECK THROTTLE BODY ASSEMBLY
(a) Check for deposits around the throttle valve and throttle valve condition.
OK:
No deposits around throttle valve and throttle valve moves smoothly.
NG -- REPAIR OR REPLACE THROTTLE BODY ASSY
OK -- Continue to next step.

13. REPLACE ECM
(a) Replace the ECM Components.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
14. REPAIR OR REPLACE THROTTLE BODY ASSY
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
15. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
NOTE:
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) Switch the ECM from normal mode to check mode using the Techstream Check Mode Procedure.
(f) Start the engine to idle for a minute.
OK:
Stable fast idling.
(g) Read the DTCs.
OK:
No DTC output.
NEXT -- END