- Valve timing
- OCV for intake camshaft
- OCV filter
- Intake camshaft timing gear
- ECM
| Last Modified: 11-29-2007 | 1.6 C | |
| Service Category: Engine/Hybrid System | Section: Engine Control | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM000000PDU05QX |
| Title: 3UR-FE ENGINE CONTROL: SFI SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
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.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
P0011 P0021 |
Intake valve timing is not adjusted in valve timing advance range (1 trip detection logic) |
|
|
P0012 P0022 |
Intake valve timing is not adjusted in valve timing retard range (2 trip detection logic) |
|
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 stored when the following conditions 1, 2 and 3 are met:
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:
MONITOR STRATEGY
|
Related DTCs |
P0011: Advanced camshaft timing (for Bank 1) P0012: Retarded camshaft timing (for Bank 1) P0021: Advanced camshaft timing (for Bank 2) P0022: Retarded camshaft timing (for Bank 2) |
|
Required Sensors/Components (Main) |
VVT OCV and VVT Actuator |
|
Required Sensors/Components (Related) |
Crankshaft position sensor, Camshaft position sensor and Engine coolant temperature sensor |
|
Frequency of Operation |
Once per driving cycle |
|
Duration |
Within 10 seconds |
|
MIL Operation |
Advanced camshaft timing: Immediate Retarded camshaft timing: 2 driving cycles |
|
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
|
Monitor runs whenever following DTCs not present |
P0102 - P0103 (MAF meter) P0115 - P0118 (ECT sensor) P0125 (Insufficient ECT for Closed Loop) P0335 (CKP sensor) P0351 - P0358 (Igniter) |
|
Battery voltage |
11 V or more |
|
Engine RPM |
500 to 4000 rpm |
|
ECT |
75 to 100°C (167 to 212°F) |
TYPICAL MALFUNCTION THRESHOLDS
Advanced Camshaft Timing
|
Valve timing |
No change at advanced valve timing |
Retarded Camshaft Timing
|
Valve timing |
No change at retarded valve 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
Refer to DTC P0010
.
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.
|
Abnormal Bank |
Advanced Timing Over (Valve Timing is Out of Specified Range) |
Retarded Timing Over (Valve Timing is Out of Specified Range) |
|---|---|---|
|
Bank 1 |
P0011 |
P0012 |
|
Bank 2 |
P0021 |
P0022 |
- 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
|
Result |
Proceed to |
|---|---|
|
P0011, P0012, P0021 or P0022 is output |
A |
|
P0011, P0012, P0021 or P0022 and other DTCs are output |
B |
HINT:
If any DTCs other than P0011, P0012, P0021 or P0022 are output, troubleshoot those DTCs first.
|
|
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:
|
Tester Operation |
Specified Condition |
|---|---|
|
OCV OFF |
Normal engine speed |
|
OCV ON |
Soon after OCV switched from OFF to ON, engine idles roughly or stalls |
|
|
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
.
(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.
|
|
5. |
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.
|
|
6. |
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:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
1 - 2 |
20°C (68°F) |
6.9 to 7.9 Ω |
(c) Apply positive (+) battery voltage to terminal 1 and negative (-) battery voltage to terminal 2. Check the valve operation.
OK:
Valve moves quickly.
|
|
7. |
INSPECT OIL CONTROL VALVE FILTER |
(a) Remove the OCV filter
.
(b) Check that the filter is not clogged.
OK:
Filter is not clogged.
|
|
8. |
REPLACE CAMSHAFT TIMING GEAR |
(a) Replace the camshaft timing gear
.
|
|
13. |
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
.
(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.
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