| DTC Code | DTC Name |
|---|---|
| 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.
Note
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.
Tech Tips
Idle speed control learning* is performed when the engine is warmed up and has been idling for 5 minutes.
*: Refer to Initialization.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P050A | Cold Start Idle Air Control System Performance | Insufficient mass air flow after a cold start (2 trip detection logic). |
|
Comes on | DTC stored |
MONITOR STRATEGY
| Required Sensors/Components (Main) | Throttle body with motor assembly |
| Required Sensors/Components (Related) | Engine coolant temperature sensor Mass air flow meter sub-assembly |
| Frequency of Operation | Once per driving cycle |
TYPICAL MALFUNCTION THRESHOLDS
| Accumulated mass air flow | Less than 30 g (varies with engine coolant temperature) |
CONFIRMATION DRIVING PATTERN
Connect the GTS to the DLC3.
Turn the power switch on (IG) and turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Put the engine in inspection mode (maintenance mode).
Start the engine and warm it up for 5 minutes or more.
Stop the engine.
Leave the vehicle outside overnight.
Turn the power switch on (IG) and turn the GTS on [A].
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
Check that "Coolant Temp" in the Data List is within the range of -10 to 50°C (14 to 122°F).
Put the engine in inspection mode (maintenance mode).
Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the freeze frame data.
Idle the engine for 1 minute or more [B].
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the pending DTC.
Tech Tips
If a pending DTC is output, the system is malfunctioning.
If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P050A.
Check the DTC judgment result.
| GTS Display | Description |
|---|---|
| NORMAL |
|
| ABNORMAL |
|
| INCOMPLETE |
|
| N/A |
|
Tech Tips
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] and [B].
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following procedure.
Tech Tips
Read freeze frame data using the GTS. 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 moving or stationary, 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
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTCs.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If any DTCs other than P050A are output, troubleshoot those DTCs first.
| B |
|
GO TO DTC CHART Click here |
| A |
|
READ VALUE USING GTS (FUEL TRIM)
Tech Tips
Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter sub-assembly.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
Start the engine.
Enter the following menus: Powertrain / Engine and ECT / Data List / Ptrl AF Control / Short FT B1S1 and Long FT B1S1.
| Tester Display |
|---|
| Short FT B1S1 |
| Long FT B1S1 |
Read the values displayed on the GTS at engine idle.
Add together the Short FT B1S1 and Long FT B1S1 values to obtain the total fuel trim.
| Standard |
|---|
| The total of the Short FT B1S1 and Long FT B1S1 values is between -20% and 20%. |
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK PCV SYSTEM Click here |
| OK |
|
INSPECT THROTTLE BODY WITH MOTOR ASSEMBLY (THROTTLE VALVE)
Inspect that there are no deposits around the throttle valve and throttle valve condition.
| OK |
|---|
| No deposits around the throttle valve and throttle valve moves smoothly. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
Tech Tips
The A/C switch and all accessory switches should be off.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Primary / MAP and Throttle Idle Position.
| Active Test Display |
|---|
| Control the EGR Step Position |
| Data List Display |
|---|
| MAP |
| Throttle Idle Position |
Confirm that the Throttle Idle Position is ON and check the MAP values in the Data List while performing the Active Test.
Tech Tips
Do not leave the EGR valve open for 10 seconds or more during the Active Test.
Be sure to return the EGR valve to step 0 when the Active Test is completed.
Do not open the EGR valve 30 steps or more during the Active Test.
| OK |
|---|
| MAP change in response to EGR step position when Throttle Idle Position is ON in Data List. |
| Standard | ||||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Tech Tips
While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.
Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO STEP 14 Click here |
| NG |
|
INSPECT EGR VALVE ASSEMBLY
Remove the EGR valve assembly.
Check if the EGR valve is stuck open.
| OK |
|---|
| EGR valve is tightly closed. |
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO STEP 14 Click here |
| NG |
|
GO TO STEP 16 Click here |
REPAIR OR REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY
Repair or replace the throttle body with motor assembly.
Tech Tips
Perform "Inspection After Repair" after replacing the throttle body with motor assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 20 Click here |
CHECK PCV SYSTEM
Check the PCV hose connections.
| OK |
|---|
| PCV valve and hose are connected correctly and are not damaged. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE PCV HOSE Click here |
| OK |
|
CHECK INTAKE SYSTEM
Check the intake system for vacuum leaks.
| OK |
|---|
| No leaks from intake system. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE INTAKE SYSTEM Click here |
| OK |
|
CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
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. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
Tech Tips
The A/C switch and all accessory switches should be off.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Primary / MAP and Throttle Idle Position.
| Active Test Display |
|---|
| Control the EGR Step Position |
| Data List Display |
|---|
| MAP |
| Throttle Idle Position |
Confirm that the Throttle Idle Position is ON and check the MAP values in the Data List while performing the Active Test.
Tech Tips
Do not leave the EGR valve open for 10 seconds or more during the Active Test.
Be sure to return the EGR valve to step 0 when the Active Test is completed.
Do not open the EGR valve 30 steps or more during the Active Test.
| OK |
|---|
| MAP change in response to EGR step position when Throttle Idle Position is ON in Data List. |
| Standard | ||||||||
|---|---|---|---|---|---|---|---|---|
|
||||||||
Tech Tips
While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.
Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.
| Result | |||
|---|---|---|---|
|
| OK |
|
GO TO STEP 12 Click here |
| NG |
|
INSPECT EGR VALVE ASSEMBLY
Remove the EGR valve assembly.
Check if the EGR valve is stuck open.
| OK |
|---|
| EGR valve is tightly closed. |
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE EGR VALVE ASSEMBLY Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE VVT LINEAR)
Operate the VVT system through the Active Test, and check if the VVT system is operating normally.
Perform the Active Test, referring to DTC P0011 Procedure.
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK AND REPAIR VVT SYSTEM Click here |
| OK |
|
READ VALUE USING GTS (MAF)
| Result | |||
|---|---|---|---|
|
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
Start the engine.
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / MAF, Coolant Temp and Engine Speed.
| Tester Display |
|---|
| Engine Speed |
| MAF |
| Coolant Temp |
Allow the engine to idle until Coolant Temp reaches 75°C (167°F) or higher.
Read MAF with the engine speed at 2500 rpm.
| Standard | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
During charging control, the engine speed is set at idle. Therefore, the engine speed does not increase when depressing the accelerator pedal. In this case, read the Data List item after charging control has completed.
| Result | |||
|---|---|---|---|
|
| NG |
|
GO TO STEP 21 Click here |
| OK |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
Note
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
| Tester Display |
|---|
| Coolant Temp |
Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
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.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input the DTC: P050A.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
CHECK FOR INTERMITTENT PROBLEMS Click here |
| B |
|
GO TO STEP 21 Click here |
CHECK AND REPAIR VVT SYSTEM
Check and repair the VVT system.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 20 Click here |
REPLACE EGR VALVE ASSEMBLY
Replace the EGR valve assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 20 Click here |
REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
Replace the air cleaner filter element sub-assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 20 Click here |
REPAIR OR REPLACE INTAKE SYSTEM
Repair or replace the intake system.
Tech Tips
Perform "Inspection After Repair" after repairing or replacing the intake system.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 20 Click here |
REPAIR OR REPLACE PCV HOSE
Repair or replace PCV valve or hose.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
Note
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
| Tester Display |
|---|
| Coolant Temp |
Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
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.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input the DTC: P050A.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
END |
| B |
|
CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY CONNECTOR CONNECTION)
Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM.
Tech Tips
Repair any problems.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
Note
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
| Tester Display |
|---|
| Coolant Temp |
Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
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.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input the DTC: P050A.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
END |
| A |
|
CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)
| Result | |||
|---|---|---|---|
|
Disconnect the mass air flow meter sub-assembly connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
REPLACE INTAKE MASS AIR FLOW METER SUB-ASSEMBLY
Replace the mass air flow meter sub-assembly.
Tech Tips
If the result of the inspection performed in step 13 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.
| Result | ||
|---|---|---|
|
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Tech Tips
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Clear the DTCs.
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
| Tester Display |
|---|
| Coolant Temp |
Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
Put the engine in inspection mode (maintenance mode).
| Tester Display |
|---|
| Inspection Mode |
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.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input the DTC: P050A.
Check the DTC judgment result.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
END |
| B |
|
REPLACE ECM Click here |