Toyota Sienna Service Manual: Air Intake Control Circuit
DESCRIPTION
The air cleaner is equipped with two inlets, one of which is opened or closed by the Air Intake Control Valve (AICV). This system reduces intake noise and increases engine power at low-to-high engine speed range.
When the engine is operating in the low-to-mid speed range, this control operates the AICV to close one of the air cleaner inlets. When the engine speed is more than 3600 rpm and the opening angle of the throttle valve is more than 60, the ECM activates the VSV and opens the AICV.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 PERFORM ACTIVE TEST BY INTELLIGENT TESTER (VSV FOR AICV)
- Turn the ignition switch to the ON position and turn the intelligent tester on.
- Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / INTAKE CTL VSV1 and operate the VSV for AICV.
- Check the operation of the VSV when the VSV is operated by the intelligent tester.
Standard
2 CHECK VSV (FOR AICV)
- Inspect the intake air control valve assembly
3 CHECK HARNESS AND CONNECTOR (VSV FOR AICV - ECM)
- Check the wire harness between the VSV for AICV connector and the ECM connector.
- Disconnect the V2 VSV for AICV connector.
- Disconnect the E9 ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance: Check for open
Check for short
- Reconnect the ECM connector
4 INSPECT FUSE (EFI NO. 2 FUSE)
- Check the EFI No. 2 fuse.
- Remove the EFI No. 2 fuse from the engine room junction block.
- Measure the EFI No. 2 fuse resistance.
Standard resistance: Below 1 Ω
- Reinstall the EFI No. 2 fuse.
5 CHECK HARNESS AND CONNECTOR (VSV FOR AICV - EFI RELAY)
- Check the wire harness between the VSV for AICV and the EFI relay.
- Remove the EFI relay from the engine room junction block.
- Measure the resistance according to the value(s) in the table below.
Standard resistance : Check for open
- Reconnect the VSV for AICV connector.
- Reinstall the EFI relay.
6 INSPECT VACUUM TANK
- Inspect the vacuum tank
CHECK ECM POWER SOURCE CIRCUIT
ACIS Control Circuit
DESCRIPTION
This circuit opens and closes the Intake Air Control Valve (IACV) in response
to changes in the engine
load in order to increase the intake efficiency (ACIS: Acoustic Control
Inducti ...
MIL Circuit
DESCRIPTION
The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions
detected by the ECM.
When the ignition switch is turned to the ON position, power is supplied to the
M ...
Other materials:
Fail-safe chart
1. FAIL-SAFE
This function minimizes the loss of the ECT functions
when any malfunction occurs in a sensor or solenoid.
(a) ATF (Automatic Transmission Fluid) temperature
sensor:
When the ATF temperature sensor has a
malfunction, 5th upshift is prohibited.
(b) Counter gear speed sensor NC ...
ABS Warning Light Remains ON
DESCRIPTION
If any of the following is detected, the ABS warning light remains on.
The skid control ECU connectors are disconnected from the skid control
ECU.
There is a malfunction in the skid control ECU internal circuit.
There is an open in the harness between the combination meter an ...
Pressure Control Solenoid "B" Electrical (Shift
Solenoid Valve SL2)
DESCRIPTION
Shifting from 1st to 5th is performed in combination with "ON" and "OFF"
operation of the shift solenoid
valves SL1, SL2, SL3, S4 and SR which are controlled by the ECM. If an open or
short circuit occurs in
either of the shift solenoid valves, the ECM cont ...
