Toyota Celica 2005 Repair Manual page 252

DTC P0011
DTC P0012
CIRCUIT DESCRIPTION
Refer to DTC P0010 on page DI−48.
DTC
Valve timing does not change at advanced position (1 trip
detection logic) when:
P0011
S Engine is warmed−up
S Engine speed is less than 4000 rpm
Valve timing does not change at retarded position (2 trip
detection logic) when:
P0012
S Engine is warmed−up
S Engine speed is less than 4000 rpm
MONITOR DESCRIPTION
The ECM optimizes the valve timing using the VVT (Variable Valve Timing) system to control the intake valve
camshaft. The VVT system includes the ECM, the OCV (Oil Control Valve) and the VVT controller. The ECM
sends a target "duty−cycle" control signal to the OCV. This control signal, sent to the OCV, regulates the oil
pressure applied to the VVT controller. The VVT controller can advance or retard the intake valve camshaft.
Example:
A DTC will be set if: 1) the difference between the target and actual valve timing is more than 5 degrees of
the crankshaft angle (CA) and the condition continues for more than 5 sec.; or 2) the OCV is forcibly activated
63 times or more.
Advanced cam DTCs are subject to "1 trip" detection logic.
Retarded cam DTCs are subject to "2 trip" detection logic.
MONITOR STRATEGY
Related DTCs
Required sensors/components
Frequency of operation
Duration
MIL operation
Sequence of operation
2005 CELICA (RM1131U)
DIAGNOSTICS
Camshaft Position "A" −Timing Over− Ad-
vanced or System Performance (Bank 1)
Camshaft Position "A" −Timing Over− Re-
tarded (Bank 1)
Detecting Condition
P0011
P0012
Main sensors/components
Related sensors/components
Once per drive cycle
10 sec.
P0011: Immediate
P0012: 2 driving cycles
None
− ENGINE (1ZZ−FE)
S VVT controller assembly
S OCV
S Valve timing
S ECM
VVT system advance (Bank 1)
VVT system retard (Bank 1)
Camshaft position sensor
Engine coolant temperature sensor,
Crankshaft position sensor
251
Trouble Area
DI−53
DIAIU−03