05–44
DIAGNOSTICS – SFI SYSTEM (April, 2003) 05AIH–06
DTC P0010 CAMSHAFT POSITION ”A” ACTUATOR
CIRCUIT (BANK 1)
CIRCUIT DESCRIPTION
The Variable Valve Timing (VVT) system includes the ECM, the Oil Control Valve (OCV) and the VVT control-
ler. The ECM sends a target ”duty–cycle” control signal to the OCV. This control signal, applied to the OCV,
regulates the oil pressure supplied to the VVT controller. Camshaft timing control is performed based on en-
gine operation conditions such as the intake air volume, throttle position and engine coolant temperature.
The ECM controls the OCV, based on the signals output from the sensors. The VVT controller regulates the
intake camshaft angle using oil pressure through the OCV. As result, the relative position between the cam-
shaft and the crankshaft is optimized, and the engine torque improves, fuel economy improves, and exhaust
emissions decrease under overall driving conditions. Also, the ECM detects the actual valve timing using
signals from the camshaft position sensor and the crankshaft position sensor, and performs the feedback
control. This is how target valve timing is verified by the ECM.
ECM
Crankshaft Position Sensor
Camshaft Timing
Mass Air Flow Sensor Target Valve Timing Oil Control
Valve (OCV)
Throttle Position Sensor
Feedback
Duty Control
Engine Coolant Temp. Sensor
Correction
Vehicle Speed Signal
Camshaft Position Sensor Actual Valve Timing
A71007
DTC No. DTC Detection Condition Trouble Area
Open or short in oil control valve circuit
P0010 Open or short in oil control valve circuit Oil control valve
ECM
2004 COROLLA (RM1037U)
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DIAGNOSTICS – SFI SYSTEM (April, 2003)
MONITOR DESCRIPTION
After the ECM sends the ”target” duty–cycle signal to the OCV, the ECM monitors the OCV current to estab-
lish an ”actual” duty–cycle. The ECM detects a malfunction and sets a DTC when the actual duty–cycle ratio
varies from the target duty–cycle ratio.
MONITOR STRATEGY
Related DTCs P0010 VVT oil control valve bank 1 range check
Required sensors/components OCV
Frequency of operation Continuous
Duration 1 seconds
MIL operation Immediately
Sequence of operation None
TYPICAL ENABLING CONDITIONS
Specification
Item
Minimum Maximum
The monitor will run whenever the follow-
See ”List of Disable a Monitor” (On page 05–25)
ing DTCs are not present
Battery voltage 11 V 13 V
Target duty ratio – 70 %
Starter OFF
Current cut status Not cut
TYPICAL MALFUNCTION THRESHOLDS
Detection Criteria Threshold
One of the following condition is met: (a) or (b)
Output duty ratio is 100 % (always ON)
(a) Output signal duty for OCV
despite the target duty ratio is less than 70 %
Output duty is 3 % or less
(b) Output signal duty for OCV
despite the ECM supplying the current to the OCV
COMPONENT OPERATING RANGE
Parameter Standard Value
Output signal duty for OCV Between 3 % and 100 %
2004 COROLLA (RM1037U)
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DIAGNOSTICS – SFI SYSTEM (April, 2003)
WIRING DIAGRAM
C2 ECM
Camshaft Timing Oil
Control Valve
1 15
Y
E3 OCV+
14
2 B–Y
E3 OCV–
A59779
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand–held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, the air–fuel ratio was lean or rich,
etc. at the time of the malfunction.
Hand–held tester:
1 PERFORM ACTIVE TEST BY HAND–HELD TESTER(OPERATE OCV)
(a) Connect the hand–held tester to the DLC3.
(b) Start the engine and warm it up.
(c) Turn the ignition switch ON and push the hand–held tester main switch ON.
(d) Select the item ”DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / VVT CTRL B1”.
(e) Check the engine speed when operating the Oil control valve (OCV) by the hand–held tester.
Standard:
Tester Operation Specified Condition
OCV is OFF Normal engine speed
OCV is ON Rough idle or engine stall
OK CHECK FOR INTERMITTENT PROBLEMS
(See page 05–41)
NG
2 INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSY(OCV)
(See page 10–2)
NG REPLACE CAMSHAFT TIMING OIL CONTROL
VALVE ASSY
OK
2004 COROLLA (RM1037U)
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DIAGNOSTICS – SFI SYSTEM (April, 2003)
3 INSPECT ECM(OCV SIGNAL)
(a) Inspection using the oscilloscope.
(b) During idling, check the waveform between the terminals
E3
of the E3 ECM connector.
Standard:
Tester Connection Specified Condition
OCV+ (E3–15) – OCV– (E3–14) Correct waveform is as shown
OCV + OCV–
OCV Signal Waveform
5 V/
Division
GND
1 msec./Division
A79111 NG REPLACE ECM (See page 10–11)
OK
4 CHECK HARNESS AND CONNECTOR(CAMSHAFT TIMING OIL CONTROL VALVE
(OCV) – ECM)
Wire Harness Side: (a) Disconnect the C2 camshaft timing oil control valve con-
Camshaft Timing Oil Control Valve nector.
C2 Connector
(b) Disconnect the E3 ECM connector.
(c) Check the resistance between the wire harness side con-
nectors.
Standard (Check for open):
Tester Connection Specified Condition
Oil control valve (C2–1) – OCV+ (E3–15)
Front View Below 1 Ω
A54386 Oil control valve (C2–2) – OCV– (E3–14)
Standard (Check for short):
Tester Connection Specified Condition
Oil control valve (C2–1) or OCV+ (E3–15) – Body ground
10 kΩ or higher
E3 Oil control valve (C2–2) or OCV– (E3–14) – Body ground
(d) Reconnect the camshaft timing oil control valve connec-
tor.
(e) Reconnect the ECM connector.
NG REPAIR OR REPLACE HARNESS OR
OCV+ OCV–
CONNECTOR
ECM Connector A65743
OK
CHECK FOR INTERMITTENT PROBLEMS (See page 05–41 )
2004 COROLLA (RM1037U)
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DIAGNOSTICS – SFI SYSTEM (April, 2003)
OBDII scan tool (excluding hand–held tester):
1 INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSY(OPERATE OCV)
Component Side: (a) Disconnect the C2 camshaft timing oil control valve con-
Camshaft Timing Oil Control Valve nector.
(b) Apply positive battery voltage between the terminals of
C2
the camshaft timing oil control valve.
(c) Check the engine speed.
Standard:
Engine speed is rough idle or engine is stalled.
(–) (+)
(d) Reconnect the camshaft timing oil control valve connec-
Front View
A76968 tor.
NG REPLACE CAMSHAFT TIMING OIL CONTROL
VALVE ASSY
OK
2 INSPECT ECM(OCV SIGNAL)
(a) Inspection using the oscilloscope.
(b) During idling, check the waveform between the terminals
E3
of the E3 ECM connector.
Standard:
Tester Connection Specified Condition
OCV+ (E3–15) – OCV– (E3–14) Correct waveform is as shown
OCV + OCV–
OCV Signal Waveform
5 V/
Division
GND
1 msec./Division
A79111
NG REPLACE ECM (See page 10–11)
OK
2004 COROLLA (RM1037U)
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DIAGNOSTICS – SFI SYSTEM (April, 2003)
3 CHECK HARNESS AND CONNECTOR(CAMSHAFT TIMING OIL CONTROL VALVE
(OCV) – ECM)
Wire Harness Side: (a) Disconnect the C2 camshaft timing oil control valve con-
Camshaft Timing Oil Control Valve nector.
C2 Connector
(b) Disconnect the E3 ECM connector.
(c) Check the resistance between the wire harness side con-
nectors.
Standard (Check for open):
Tester Connection Specified Condition
Oil control valve (C2–1) – OCV+ (E3–15)
Front View Below 1 Ω
A54386 Oil control valve (C2–2) – OCV– (E3–14)
Standard (Check for short):
Tester Connection Specified Condition
Oil control valve (C2–1) or OCV+ (E3–15) – Body ground
10 kΩ or higher
E3 Oil control valve (C2–2) or OCV– (E3–14) – Body ground
(d) Reconnect the camshaft timing oil control valve connec-
tor.
(e) Reconnect the ECM connector.
OCV+ OCV–
NG REPAIR OR REPLACE HARNESS OR
ECM Connector A65743 CONNECTOR
OK
CHECK FOR INTERMITTENT PROBLEMS (See page 05–41 )
2004 COROLLA (RM1037U)
Author: Date: 214
