P050A
3MZ-FE 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 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.
NOTE: 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
INSPECTION PROCEDURE
HINT: When viewed from the rear of the engine assembly, Bank 1 is on the left side and Bank 2 is on the right side.
PROCEDURE
1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Select the following the menu items: 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
OK -- Continue to next step.
2. READ VALUE OF TECHSTREAM (FUEL TRIM)
HINT: Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position and turn the tester on.
(c) Enter the following menus: Powertrain / Engine and ECT / Data List / A/F Control System / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.
(d) Read the values displayed on the tester.
(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.
OK:
Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.
NG -- PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)
OK -- Continue to next step.
3. CHECK 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. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)
(a) Connect Techstream to the DLC3.
(b) Start the engine and turn the tester on.
(c) Warm up the engine.
(d) Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
(e) Check the engine speed while operating the Oil Control Valve (OCV) using the tester.
OK:
NG -- REPAIR OR REPLACE THROTTLE BODY
OK -- Continue to next step.
5. 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.
6. CHECK AIR CLEANER FILTER
(a) Visually check that the air cleaner filter 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 (On-Vehicle Inspection).
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 (Components).
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
9. REPLACE ECM
(a) Replace the ECM (Components).
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
10. CHECK AND REPAIR VVT SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
11. REPAIR OR REPLACE PCV HOSE
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
12. REPLACE AIR CLEANER FILTER
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
13. REPAIR OR REPLACE AIR INDUCTION SYSTEM
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (DTC P050A)
14. REPLACE MASS AIR FLOW METER
(a) Replace the mass air flow meter.
NEXT -- Continue to next step.
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 Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Clear the DTCs (DTC Check / Clear).
(e) Switch the ECM from normal mode to check mode using the tester (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