P0021
3UR-FE ENGINE CONTROL: SFI SYSTEM: P0011: Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 1)
DTC P0011 - Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 1)
DTC P0012 - Camshaft Position "A" - Timing Over-Retarded (Bank 1)
DTC P0021 - Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 2)
DTC P0022 - Camshaft Position "A" - Timing Over-Retarded (Bank 2)
DESCRIPTION
The VVT system includes the ECM, Oil Control Valve (OCV) and VVT controller. The ECM sends a target duty-cycle control signal to the OCV. This control signal regulates the oil pressure supplied to the VVT controller. Camshaft timing control is performed according to engine operating conditions such as the intake air volume, throttle valve position and engine coolant temperature. The ECM controls the OCV, based on the signals transmitted by several sensors. The VVT controller regulates the intake camshaft angle using oil pressure through the OCV. As a result, the relative positions of the camshaft and crankshaft are optimized, the engine torque and fuel economy improve, and the exhaust emissions decrease under overall driving conditions. The ECM detects the actual intake valve timing using signals from the camshaft and crankshaft position sensors, and performs feedback control. This is how the target intake valve timing is verified by the ECM.
MONITOR DESCRIPTION
The ECM optimizes the intake valve timing using the VVT (Variable Valve Timing) system to control the intake camshaft. The VVT system includes the ECM, Oil Control Valve (OCV) and VVT controller. The ECM sends a target duty-cycle control signal to the OCV. This control signal regulates the oil pressure supplied to the VVT controller. The VVT controller can advance or retard the intake camshaft.
If the difference between the target and actual intake valve timings is large, and changes in the actual intake valve timing are small, the ECM interprets this as the VVT controller stuck malfunction and store a DTC.
Example: A DTC is set when the following conditions 1 and 2 met for 10 seconds more:
1. The difference between the target and actual intake valve timing is more than 5°CA (Crankshaft Angle) and the condition continues for more than 5 seconds.
2. It takes 5 seconds or more to change the valve timing by 5°CA.
DTC P0011 and P0021 (Advanced Cam Timing) are subject to 1 trip detection logic.
DTC P0012 and P0022 (Retarded Cam Timing) are subject to 2 trip detection logic.
These DTCs indicate that the VVT controller cannot operate properly due to OCV malfunctions or the presence of foreign objects in the OCV.
The monitor will run if all of the following conditions are met:
- The engine is warm (the engine coolant temperature is 75°C [167°F] or more).
- The vehicle has been driven at more than 64 km/h (40 mph) for 3 minutes.
- The engine has idled for 3 minutes.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
Advanced Camshaft Timing
Retarded Camshaft Timing
If the difference between the target and actual camshaft timings is greater than the specified value, the ECM operates the VVT actuator.
Then, the ECM monitors the camshaft timing change for 10 seconds.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
DTC P0011, P0012, P0021 or P0022 may be set when foreign objects in the engine oil are caught in some parts of the system. The DTC will remain set even if the system returns to normal after a short time. Foreign objects are filtered out by the oil filter.
- If DTC P0011 or P0012 is displayed, check the left bank VVT system for intake camshaft circuit (for Bank 1).
- Bank 1 refers to the bank that includes No. 1 cylinder.
- If DTC P0021 or P0022 is displayed, check the right bank VVT system for intake camshaft circuit (for Bank 2).
- Bank 2 refers to the bank that does not include No. 1 cylinder.
- Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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 P0011, P0012, P0021 OR P0022)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read DTCs.
Result
HINT: If any DTCs other than P0011, P0012, P0021 or P0022 are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART
A -- Continue to next step.
2. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Turn the Techstream on.
(d) Warm up the engine.
(e) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1) or Control the VVT System (Bank 2).
(f) Check the engine speed while operating the Oil Control Valve (OCV) using the Techstream.
OK:
NG -- CHECK VALVE TIMING (CHECK FOR LOOSE AND JUMPED TOOTH OF TIMING CHAIN)
OK -- Continue to next step.
3. CHECK WHETHER DTC OUTPUT RECURS (DTC P0011, P0012, P0021 OR P0022)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear DTCs DTC Check / Clear.
(e) Start the engine and warm it up.
(f) Switch the ECM from normal mode to check mode using the Techstream.
(g) Drive the vehicle for more than 10 minutes.
(h) Read DTCs using the Techstream.
OK:
No DTC output.
NG -- CHECK VALVE TIMING (CHECK FOR LOOSE AND JUMPED TOOTH OF TIMING CHAIN)
OK -- CHECK FOR INTERMITTENT PROBLEMS
4. CHECK VALVE TIMING (CHECK FOR LOOSE AND JUMPED TOOTH OF TIMING CHAIN)
(a) Remove the cylinder head cover LH and RH.
(b) Turn the crankshaft pulley, and align its groove with the alignment mark "0" of the timing chain cover.
(c) Check that the alignment marks of the camshaft timing gears and camshaft timing exhaust gears are at the positions shown in the illustration.
OK:
Alignment marks on camshaft timing gears are aligned as shown in the illustration.
NG -- ADJUST VALVE TIMING
OK -- Continue to next step.
5. INSPECT CAMSHAFT OIL CONTROL VALVE ASSEMBLY (OCV)
(a) Remove the OCV.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
(c) Apply positive (+) battery voltage to terminal 1 and negative (-) battery voltage to terminal 2. Check the valve operation.
OK:
Valve moves quickly.
NG -- REPLACE CAMSHAFT OIL CONTROL VALVE ASSEMBLY
OK -- Continue to next step.
6. INSPECT OIL CONTROL VALVE FILTER
(a) Remove the OCV filter Disassembly.
(b) Check that the filter is not clogged.
OK:
Filter is not clogged.
NG -- CLEAN OIL CONTROL VALVE FILTER
OK -- Continue to next step.
7. REPLACE CAMSHAFT TIMING GEAR
(a) Replace the camshaft timing gear Disassembly.
NEXT -- Continue to next step.
8. CHECK WHETHER DTC OUTPUT RECURS
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear DTCs DTC Check / Clear.
(e) Start the engine and warm it up.
(f) Switch the ECM from normal mode to check mode using the Techstream.
(g) Drive the vehicle for more than 10 minutes.
(h) Read the output DTCs using the Techstream.
OK:
No DTC is output.
HINT: DTC P0011, P0012, P0021 or P0022 is output when foreign objects in the engine oil are caught in some parts of the system. These codes will stay registered even if the system returns to normal after a short time. These foreign objects are then captured by the oil filter, thus eliminating the source of the problem.
NG -- REPLACE ECM
OK -- END