DESCRIPTION
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 improves, 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
After the ECM sends the "target" duty-cycle signal to the OCV, the ECM monitors the OCV current to establish an "actual" duty-cycle. The ECM detects a malfunction and sets a DTC when the actual dutycycle ratio varies from the target duty-cycle ratio.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
COMPONENT OPERATING RANGE
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
1 PERFORM ACTIVE TEST BY CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY (OCV)
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine and turn the tester on.
(c) Warm up the engine.
(d) On the tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / VVT CTRL B1 or VVT CTRL B2.
(e) Check the engine speed while operating the Oil Control Valve (OCV) using the tester.
2 INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY
(a) Disconnect the C23 or C24 camshaft timing oil control valve (OCV) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
(c) Reconnect the OCV connector.
3 CHECK HARNESS AND CONNECTOR (OCV - ECM)
(a) Disconnect the C23 or C24 camshaft timing oil control valve (OCV) connector.
(b) Disconnect the E11 ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open)
Standard resistance (Check for short)
(d) Reconnect the OCV connector.
(e) Reconnect the ECM connector.
REPLACE ECM (See page ES-498)
On-vehicle inspection
1. INSPECT CENTER AIRBAG SENSOR ASSEMBLY
(VEHICLE NOT INVOLVED IN COLLISION)
Perform a diagnosis system check.
2. INSPECT CENTER AIRBAG SENSOR ASSEMBLY
(VEHICLE INVOLVED IN COLLISION AND AIRBAG
HAS NOT DEPLOYED)
Perform a diagnosis system check.
3. INSPECT CENTER AIRBAG ...
Power Seat Motor Circuit
DESCRIPTION
When the power seat control switch is operated, a command signal is sent to
the position control ECU
and switch assembly (power seat control switch and ECU). The front power seat
switch then controls the
appropriate seat motor as needed. This memory system does not use a seat
po ...
Axle
SST
RECOMMENDED TOOLS
HINT:
Trox is a registered trademark of Trxtron Inc.
EQUIPMENT
...