P0021

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

DTC Detection Condition:

The Variable Valve Timing (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 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

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

1. 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, the Oil Control Valve (OCV) and the VVT controller.
2. 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 timing is large, and changes in the actual intake valve timing are small, the ECM interprets this as the VVT controller stuck malfunction and sets a DTC.

Example:
A DTC is set when the given conditions procedure (1),(2) and (3) are met:
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 4.5 seconds.
2. It takes 5 seconds or more to change the valve timing by 5 °CA.
3. After given conditions (1) and (2) are met, the OCV is forcibly activated 63 times or more.

3. DTCs P0011 and P0021 (Advanced Cam Timing) are subject to 1 trip detection logic.
4. DTCs 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.
5. The monitor will not run unless the given conditions are met:
a. The engine is warm (the engine coolant temperature is 75 °C (167 °F) or more).
b. The vehicle has been driven at more than 40 mph (64 km/h) for 3 minutes.
c. The engine has idled for 3 minutes.

Wiring Diagram:

Step 1-2:

Step 2(Continued)-3:

Step 4-5:

Step 6-8:

Step 8(Continued):

INSPECTION PROCEDURE






HINT:
- If DTC P0011 or P0012 is displayed, check the bank 1 VVT system for intake side circuit.
- Bank 1 refers to the bank that includes No. 1 cylinder.
- If DTC P0021 or P0022 is displayed, check the bank 2 VVT system for intake side circuit (bank 2).
- Bank 2 refers to the bank that does not include No. 1 cylinder.
- Read freeze frame data using the intelligent tester. 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 running or stopped, 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.