Toyota Sienna Service Manual: 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 Induction System).
When the engine speed is between 0 and 4450 rpm and the throttle valve opening angle is 60° or more, the ECM supplies current to the VSV (ON status), to close the IACV. Under other conditions, the VSV is usually OFF and the IACV is open.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE VSV FOR ACIS)
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine and turn the intelligent tester on.
(c) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / INTAKE CTL VSV1. Operate the VSV for AICS.
OK: Operational noise can be heard.
2 CHECK INTAKE AIR CONTROL VALVE (OPERATION)
(a) Disconnect the V14 VSV for ACIS connector.
(b) Apply battery voltage between the terminals of the air intake valve connector.
(c) Check the air intake valve operation.
OK: Operational noise can be heard.
(d) Reconnect the VSV for ACIS connector.
3 CHECK HARNESS AND CONNECTOR (VSV FOR ACIS - ECM)
(a) Check the wire harness and connectors between the VSV for ACIS and ECM.
(1) Disconnect the V14 VSV for ACIS connector.
(2) Disconnect the E9 ECM connector.
(3) Measure the resistance according to the value(s) in the table below.
Standard resistance :
(4) Reconnect the VSV for ACIS connector.
(5) Reconnect the ECM connector.
4 INSPECT FUSE (EFI NO. 2 FUSE)
(a) Check the EFI No. 2 fuse.
(1) Remove the EFI No. 2 fuse from the engine room junction block.
(2) Measure the EFI No. 2 fuse resistance.
Standard resistance: Below 1 Ω
(3) Reinstall the EFI No. 2 fuse.
5 CHECK HARNESS AND CONNECTOR (VSV FOR ACIS - EFI RELAY)
(a) Check the wire harness between the VSV for ACIS connector and EFI relay.
(1) Remove the EFI relay from the engine room junction block.
(2) Disconnect the V14 VSV connector.
(3) Measure the resistance according to the value(s) in the table below.
Standard resistance :
(4) Reinstall the EFI relay.
(5) Reconnect the VSV connector.
CHECK ECM POWER SOURCE CIRCUIT (See page ES-437)
Cranking Holding Function Circuit
DESCRIPTION
The system detects the ignition switch's starting signal (STSW) and then
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until the ECM judges that the engine has started successfully. The purpose is t ...
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
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l ...
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Blower Motor Circuit
DESCRIPTION
The blower motor is operated by signals from the A/C amplifier. Blower motor
speed signals are
transmitted by changes in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For
example, if A is the period of
continuity in one cycl ...
Brake Switch "A" Circuit
DTC P0571 Brake Switch "A" Circuit
DESCRIPTION
When the brake pedal is depressed, the stop light switch sends a signal to
the ECM. When the ECM
receives this signal, it cancels the cruise control. The fail-safe function
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Diagnostic trouble code chart
1. DTCS FOR OCCUPANT CLASSIFICATION SYSTEM
If a trouble code is displayed during the DTC check,
check the circuit listed for the code in the table below
(proceed to the page listed for that circuit).
HINT:
When DTC B1150/23 is detected as a result of
troubleshooting for the airbag system, pe ...
