Toyota Tundra Service Manual: ACIS Control Circuit

DESCRIPTION

This circuit opens and closes the Intake Air Control Valve (IACV) in response to the engine load in order to increase the intake efficiency (ACIS: Acoustic Control Induction System).

WIRING DIAGRAM

PROCEDURE

(a) Disconnect the vacuum hose from port F on the vacuum switching valve (for ACIS).

(b) Connect the Techstream to the DLC3.

(c) Start the engine.

(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Active the VSV for Intake Control.

(e) Operate the VSV for ACIS.

(f) Check the VSV air flow when switching the VSV.

OK:

NG

GO TO STEP 4

OK

NG

REPAIR OR REPLACE VACUUM HOSES

OK

(a) Inspect the intake air control valve (See page ).

OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPLACE INTAKE MANIFOLD

(a) Inspect the vacuum switching valve (for ACIS) (See page ).

NG

REPLACE VACUUM SWITCHING VALVE (FOR ACIS)

OK

(a) Remove the EFI NO. 2 fuse from the engine room relay block.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

(c) Reinstall the EFI NO. 2 fuse.

(d) Disconnect the intake air control valve connector.

(e) Disconnect the ECM connector.

(f) Remove the integration relay from the engine room relay block.

(g) Disconnect the integration relay connector.

(h) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

OK

REPLACE ECM

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR