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 this 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.
NOTICE:
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.
HINT:
Idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
---|---|---|---|---|---|---|
P050A00 | Cold Start Idle Control System Performance | Insufficient mass air flow after a cold start (2 trip detection logic). |
| Comes on | DTC stored | SAE Code: P050A |
MONITOR STRATEGY
Related DTCs | P050A: Cold start idle air speed control system |
Required Sensors/Components (Main) | Throttle body with motor assembly |
Required Sensors/Components (Related) | Mass air flow meter sub-assembly Engine coolant temperature sensor |
Frequency of Operation | Once per driving cycle |
Duration | 10 seconds |
MIL Operation | 2 driving cycles |
Sequence of Operation | None |
TYPICAL ENABLING CONDITIONS
Monitor runs whenever the following DTCs are not stored | P0010, P0020 (VVT oil control solenoid bank 1, 2) P0011, P0021 (VVT system bank 1, 2 - advance) P0012, P0022 (VVT system bank 1, 2 - retard) P0013, P0023 (Exhaust VVT oil control solenoid bank 1, 2) P0014, P0024 (Exhaust VVT system bank 1, 2 - advance) P0015, P0025 (Exhaust VVT system bank 1, 2 - retard) P0016, P0018 (VVT system bank 1, 2 - misalignment) P0017, P0019 (Exhaust VVT system bank 1, 2 - misalignment) P0087, P0088, P0191, P0192, P0193 (Fuel pressure sensor (for high pressure side)) P0101, P0102, P0103 (Mass air flow meter) P0116, P0117, P0118 (Engine coolant temperature sensor) P011B (Engine coolant temperature/intake air temperature sensor correlation) P0121, P0122, P0123, P0222, P0223, P2135 (Throttle position sensor) P0125 (Insufficient coolant temperature for closed loop fuel control) P014C, P014D, P014E, P014F, P015A, P015B, P015C, P015D, P2195, P2196, P2197, P2198, P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2254, P2255, P2256 (Air fuel ratio sensor) P0171, P0172, P0174, P0175 (Fuel system) P0201, P0202, P0203, P0204, P0205, P0206, P062D, P21CF, P21D0, P21D1, P21D2, P21D3, P21D4 (Fuel injector) P0300 - P0306 (Misfire) P0335, P0337, P0338 (Crankshaft position sensor) P0340, P0342, P0343, P0345, P0347, P0348 (VVT sensor) P0365, P0367, P0368, P0390, P0392, P0393 (Exhaust VVT sensor) P0500 (Vehicle speed sensor) P0657, P2102, P2103, P2111, P2112, P2119 (Throttle actuator) P0705 (Shift lever position switch) P107B, P107C, P107D (Fuel pressure sensor (for low pressure side)) P11EA, P11EB, P11EC, P11ED, P11EE, P11EF, P11F0, P11F1, P219A, P219B, P219C, P219D, P219E, P219F, P21A0, P21A1 (Air-fuel ratio imbalance) P1235 (High pressure fuel pump circuit) |
Battery voltage | 8 V or higher |
Time after engine start | 3 seconds or more |
Starter | Off |
Engine coolant temperature at engine start | -10°C (14°F) or higher |
Engine coolant temperature | -10°C (14°F) or higher, and less than 50°C (122°F) |
Engine idling time | 3 seconds or more |
Fuel-cut | Off |
Vehicle speed | Less than 3 km/h (1.875 mph) |
Time after shift position changed | 1 second or more |
Atmospheric pressure | 76 kPa(abs) [11.02 psi(abs)] or higher |
TYPICAL MALFUNCTION THRESHOLDS
Accumulated mass air flow | Less than 103.1 g (varies with engine coolant temperature, engine coolant temperature at engine start and ignition timing) |
CONFIRMATION DRIVING PATTERN
HINT:
Click here
Click here
HINT:
Techstream Display | Description |
---|---|
NORMAL |
|
ABNORMAL |
|
INCOMPLETE |
|
HINT:
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
WIRING DIAGRAM
Refer to DTC P010012.
Click here
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following 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 P050A00) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Powertrain > Engine > Trouble Codes Result | Proceed to |
---|---|
DTC P050A00 is output | A |
DTC P050A00 and other DTCs are output | B |
HINT:
If any DTCs other than P050A00 are output, troubleshoot those DTCs first.
B | GO TO DTC CHART |
|
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) Start the engine.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / Short FT B1S1, Long FT B1S1, Short FT B2S1 and Long FT B2S1.
Powertrain > Engine > Data List Tester Display |
---|
Short FT B1S1 |
Short FT B2S1 |
Long FT B1S1 |
Long FT B2S1 |
(e) Read the values displayed on the Techstream at engine idle.
(f) Add together the Short FT B1S1 and Long FT B1S1 values, and the Short FT B2S1 and Long FT B2S1 values to obtain the total fuel trim.
Standard:
Techstream Display | Specified Condition |
---|---|
Total of the Short FT B1S1 and Long FT B1S1 | Between -20 and 20% |
Total of the Short FT B2S1 and Long FT B2S1 | Between -20 and 20% |
NG | GO TO STEP 5 |
|
3. | INSPECT THROTTLE BODY WITH MOTOR ASSEMBLY (THROTTLE VALVE) |
(a) Check 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.
OK | GO TO STEP 10 |
|
4. | REPAIR OR REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY |
(a) Repair or replace the throttle body with motor assembly.
Click here
HINT:
Perform "Inspection After Repair" after repairing or replacing the throttle body with motor assembly.
Click here
NEXT | GO TO STEP 15 |
5. | CHECK PCV SYSTEM |
(a) Check the PCV hose connections.
Click here
OK:
PCV valve and hose are connected correctly and are not damaged.
NG | GO TO STEP 14 |
|
6. | CHECK INTAKE SYSTEM |
(a) Check the intake system for vacuum leaks.
Click here
OK:
No leaks from the intake system.
NG | GO TO STEP 13 |
|
7. | CHECK 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:
The air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.
NG | GO TO STEP 12 |
|
8. | PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY) |
(a) Operate the VVT system through the Active Test, and check if the VVT system is operating normally.
(1) Perform the Active Test, referring to DTC P001100 Procedure (VVT system for intake camshaft).
Click here
(2) Perform the Active Test, referring to DTC P001400 Procedure (VVT system for exhaust camshaft).
Click here
NG | GO TO STEP 11 |
|
9. | READ VALUE USING TECHSTREAM (MASS AIR FLOW SENSOR) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Mass Air Flow Sensor and Coolant Temperature.
Powertrain > Engine > Data List Tester Display |
---|
Engine Speed |
Mass Air Flow Sensor |
Coolant Temperature |
(e) Allow the engine to idle until Coolant Temperature reaches 75°C (167°F) or higher.
(f) Read Mass Air Flow Sensor while maintaining an engine speed of 3000 rpm.
Standard:
Techstream Display | Condition | Specified Condition |
---|---|---|
Mass Air Flow Sensor | Engine warmed up Shift lever position: P A/C: Off Engine Speed: 3000 rpm | Between 10.6 gm/sec and 15.8 gm/sec |
NG | GO TO STEP 16 |
|
10. | CHECK WHETHER DTC OUTPUT RECURS (DTC P050A00) |
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 engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG).
(g) Turn the Techstream on.
(h) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
Powertrain > Engine > Data List Tester Display |
---|
Coolant Temperature |
(i) Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
(j) 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.
(k) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(l) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Powertrain > Engine > Utility Tester Display |
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All Readiness |
(m) Input the DTC: P050A00.
(n) Check the DTC judgment result.
Result | Proceed to |
---|---|
NORMAL (DTCs are not output) | A |
ABNORMAL (DTC P050A00 is output) | B |
A | CHECK FOR INTERMITTENT PROBLEMS |
B | GO TO STEP 16 |
11. | CHECK AND REPAIR VVT SYSTEM |
(a) Check and repair the VVT system.
HINT:
Click here
Click here
NEXT | GO TO STEP 15 |
12. | REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY |
(a) Replace the air cleaner filter element sub-assembly.
NEXT | GO TO STEP 15 |
13. | REPAIR OR REPLACE INTAKE SYSTEM |
(a) Repair or replace the intake system.
HINT:
Perform "Inspection After Repair" after repairing or replacing the intake system.
Click here
NEXT | GO TO STEP 15 |
14. | REPAIR OR REPLACE PCV HOSE |
(a) Repair or replace the PCV valve or hose.
|
15. | CHECK WHETHER DTC OUTPUT RECURS (DTC P050A00) |
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 engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG).
(g) Turn the Techstream on.
(h) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
Powertrain > Engine > Data List Tester Display |
---|
Coolant Temperature |
(i) Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
(j) 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.
(k) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(l) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Powertrain > Engine > Utility Tester Display |
---|
All Readiness |
(m) Input the DTC: P050A00.
(n) Check the DTC judgment result.
Result | Proceed to |
---|---|
NORMAL (DTCs are not output) | A |
ABNORMAL (DTC P050A00 is output) | B |
A | END |
|
16. | CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY CONNECTOR CONNECTION) |
(a) Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM.
Click here
HINT:
Repair any problems.
|
17. | CHECK WHETHER DTC OUTPUT RECURS (DTC P050A00) |
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 engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG).
(g) Turn the Techstream on.
(h) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
Powertrain > Engine > Data List Tester Display |
---|
Coolant Temperature |
(i) Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
(j) 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.
(k) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(l) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Powertrain > Engine > Utility Tester Display |
---|
All Readiness |
(m) Input the DTC: P050A00.
(n) Check the DTC judgment result.
Result | Proceed to |
---|---|
NORMAL (DTCs are not output) | A |
ABNORMAL (DTC P050A00 is output) | B |
A | END |
|
18. | 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:
Tester Connection | Condition | Specified Condition |
---|---|---|
D9-3 (5V) - D2-90 (VC) | Always | Below 1 Ω |
D9-1 (FG) - D2-116 (VG) | Always | Below 1 Ω |
D9-2 (E2G) - D2-115 (E2G) | Always | Below 1 Ω |
D9-3 (5V) or D2-90 (VC) - Body ground and other terminals | Always | 10 kΩ or higher |
D9-1 (FG) or D2-116 (VG) - Body ground and other terminals | Always | 10 kΩ or higher |
D9-2 (E2G) or D2-115 (E2G) - Body ground and other terminals | Always | 10 kΩ or higher |
NG | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
19. | REPLACE MASS AIR FLOW METER SUB-ASSEMBLY |
(a) Replace the mass air flow meter sub-assembly.
Click here
HINT:
Click here
|
20. | CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED |
HINT:
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 engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG).
(g) Turn the Techstream on.
(h) Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
Powertrain > Engine > Data List Tester Display |
---|
Coolant Temperature |
(i) Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
(j) 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.
(k) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
(l) Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Powertrain > Engine > Utility Tester Display |
---|
All Readiness |
(m) Input the DTC: P050A00.
(n) Check the DTC judgment result.
Result | Proceed to |
---|---|
NORMAL (DTCs are not output) | A |
ABNORMAL (DTC P050A00 is output) | B |
A | END |
B | REPLACE ECM |
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