P050A
2ZR-FXE 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 at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC can be 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 below 50°C (122°F), the ECM measures the accumulated mass air flow at idle. 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 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.
NOTICE:
When the negative (-) auxiliary battery terminal is disconnected during inspection or repairs, the idle speed control (ISC) learned values are cleared. Idle speed control learning needs to be performed before this DTC can be stored. To perform idle speed control learning, the engine must be warmed up by allowing it to idle for 5 minutes. For idle speed control 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 below 50°C (122°F) before allowing it to continue running for the 5 minute learning period.
HINT
The idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.
MONITOR DESCRIPTION
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG) and turn the Techstream on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.
4. Turn the power switch off and wait for 30 seconds.
5. Turn the power switch on (IG) and turn the Techstream on [A].
6. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Coolant Temp.
7. Check that "Coolant Temp" in the Data List is within the range of -10 to 50°C (14 to 122°F).
8. Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
9. Start the engine and warm it up until the coolant temperature is the same as the coolant temperature in the freeze frame data.
10. Idle the engine for 1 minute or more.
11. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [B].
12. 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.
13. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
14. Input the DTC: P050A.
15. Check the DTC judgment result.
HINT
- 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 UNKNOWN, idle the engine for 3 minutes, let the engine cool down, and then perform steps [A] through [B].
16. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
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 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 ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following the menus: Powertrain / Engine and ECT / 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 SFI System
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 sub-assembly.
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG) and turn the Techstream on.
(c) Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
(d) Start the engine.
(e) Enter the following menus: Powertrain / Engine and ECT / Data List / Gas A/F Control / Short FT #1 and Long FT #1.
(f) Read the values displayed on the Techstream.
(g) 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 -- CHECK PCV HOSE (HOSE CONNECTIONS)
OK -- Continue to next step.
3. INSPECT 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 ASSEMBLY
OK -- Continue to next step.
4. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
HINT
The A/C switch and all accessory switches should be off.
(f) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / Primary / Throttle Idle Position and MAP.
(g) Confirm that the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.
HINT
- Do not leave the EGR valve open for 10 seconds or more during Active Test.
- Be sure to return the EGR valve to step 0 when Active Test is completed.
- Do not open the EGR valve 30 steps or more during the Active Test.
OK:
MAP and idling condition change in response to EGR step position as follows.
Standard:
HINT
During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in EGR valve.
NG -- INSPECT EGR VALVE ASSEMBLY
OK -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
5. INSPECT EGR VALVE ASSEMBLY
(a) Remove the EGR valve assembly Removal.
(b) Check if the EGR valve is stuck open.
OK:
EGR valve is tightly closed.
NG -- REPLACE EGR VALVE ASSEMBLY
OK -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
6. REPAIR OR REPLACE THROTTLE BODY ASSEMBLY
(a) Repair or replace the throttle body assembly Removal.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
7. CHECK PCV HOSE (HOSE CONNECTIONS)
(a) Check the PCV hose connections Intake System.
OK:
PCV hose is connected correctly and is not damaged.
NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.
8. CHECK INTAKE SYSTEM
(a) Check the intake system for vacuum leaks Intake System.
OK:
No leaks in intake system.
NG -- REPAIR OR REPLACE INTAKE SYSTEM
OK -- Continue to next step.
9. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
(a) Visually check that the air cleaner filter element sub-assembly 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.
10. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Put the engine in inspection mode (maintenance mode) Component Tests and General Diagnostics.
(e) Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
HINT
The A/C switch and all accessory switches should be off.
(f) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / Primary / Throttle Idle Position and MAP.
(g) Confirm that the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.
HINT
- Do not leave the EGR valve open for 10 seconds or more during Active Test.
- Be sure to return the EGR valve to step 0 when Active Test is completed.
- Do not open the EGR valve 30 steps or more during the Active Test.
OK:
MAP and idling condition change in response to EGR step position as follows.
Standard:
HINT
During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in EGR valve.
NG -- INSPECT EGR VALVE ASSEMBLY
OK -- PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAMSHAFT TIMING OIL CONTROL VALVE)
11. INSPECT EGR VALVE ASSEMBLY
(a) Remove the EGR valve assembly Removal.
(b) Check if the EGR valve is stuck open.
OK:
EGR valve is tightly closed.
NG -- REPLACE EGR VALVE ASSEMBLY
OK -- Continue to next step.
12. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAMSHAFT TIMING OIL CONTROL VALVE) P0010
NG -- CHECK AND REPAIR VVT SYSTEM
OK -- Continue to next step.
13. READ VALUE USING TECHSTREAM (MAF) P0171
NG -- CHECK HARNESS AND CONNECTOR
OK -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
14. REPAIR OR REPLACE PCV HOSE
(a) Repair or replace the PCV hose.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
15. REPAIR OR REPLACE INTAKE SYSTEM
(a) Repair or replace the intake system.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
16. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
(a) Replace the air cleaner filter element sub-assembly.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
17. REPLACE EGR VALVE ASSEMBLY
(a) Replace the EGR valve assembly Removal.
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
18. CHECK AND REPAIR VVT SYSTEM
(a) Check and repair the VVT system.
NEXT -- Continue to next step.
19. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
NOTICE:
In this operation, the engine must be cold (approximately the same level as the engine coolant temperature recorded in the freeze frame data).
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the power switch off and wait for 30 seconds.
(f) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(h) Input the DTC: P050A.
(i) Check the DTC judgment result.
Result
B -- CHECK HARNESS AND CONNECTOR
A -- CHECK FOR INTERMITTENT PROBLEMS Check For Intermittent Problems
20. CHECK HARNESS AND CONNECTOR
(a) Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM Electronic Circuit Inspection Procedure.
HINT
Repair any problems.
NEXT -- Continue to next step.
21. CHECK WHETHER DTC OUTPUT RECURS
NOTICE:
In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the power switch off and wait for 30 seconds.
(f) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(h) Check the DTC judgment result.
Result
B -- END
A -- Continue to next step.
22. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)
(a) Disconnect the mass air flow meter sub-assembly connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
23. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY
(a) Replace the mass air flow meter sub-assembly Removal.
HINT
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.
NEXT -- Continue to next step.
24. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
NOTICE:
In this operation, the engine must be cold (approximately the same level as the engine coolant temperature recorded in the freeze frame data).
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(e) Turn the power switch off and wait for 30 seconds.
(f) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(g) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(h) Input the DTC: P050A.
(i) Check the DTC judgment result.
Result
B -- REPLACE ECM Removal
A -- END