Page 697 of 4323
B17411
+B E1(+)
(±)E6
E4
B17411
IGSW (+)E4
± DIAGNOSTICSENGINE
DI±495
689 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals +B and E1 of ECM connector.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals +B and E1 of the ECM
connectors.
OK:
Standard: 9 to 14 V
OK Proceed to next circuit inspection shown in the
Problem symptoms table (See page BE±2).
NG
2 Check for open in harness and connector between terminal E1 of ECM and body
ground (See page IN±35).
NG Repair or replace harness or connector.
OK
3 Check voltage between terminal IGSW of ECM connector and body ground.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal IGSW of the ECM con-
nector and body ground.
OK:
Standard: 9 to 14 V
OK Go to step 6.
NG
Page 698 of 4323
A21560
IGN1 Instrument
Panel J/B:
I08467
LOCKACC
ON
START
DI±496
± DIAGNOSTICSENGINE
690 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check IGN1 fuse.
PREPARATION:
Remove the IGN1 fuse from the instrument panel J/B.
CHECK:
Check the resistance of the IGN1 fuse.
OK:
Below 1 W
NG Check for short in all harness and components
connected to IGN1 fuse.
OK
5 Check ignition switch (See page BE±24).
PREPARATION:
(a) Remove the lower finish panel.
(b) Disconnect the ignition switch connector.
CHECK:
Check resistance between terminals.
OK:
Standard:
Switch PositionTerminal ConditionSpecified Condition
LOCKAlways10 kW or more
ACC1 ± 3Below 1 W
ON1 ± 2 ± 3
5 ± 6Below 1 W
START1 ± 2
4 ± 5 ± 6Below 1 W
NG Replace ignition switch.
OK
Check and repair harness and connector be-
tween IGN fuse and ECM.
Page 699 of 4323
B17411MREL(+)E4
Engine Room
J/B:
A21381
EFI No. 1
Fuse
± DIAGNOSTICSENGINE
DI±497
691 Author: Date:
2005 SEQUOIA (RM1146U)
6 Check voltage between terminal MREL of ECM connector and body ground.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal MREL of the ECM con-
nector and body ground.
OK:
Standard: 9 to 14 V
NG Replace ECM (See page SF±80).
OK
7 Check EFI No. 1 fuse of engine room J/B.
PREPARATION:
Remove the EFI No. 1 fuse from the engine room J/B.
CHECK:
Check resistance of EFI No. 1 fuse.
OK:
Below 1 W
NG Check for short in all harness and components
connected to EFI No. 1 fuse.
OK
Page 700 of 4323
A19288
EFI Relay
B17417
E4
MREL ECM Connector
DI±498
± DIAGNOSTICSENGINE
692 Author: Date:
2005 SEQUOIA (RM1146U)
8 Check EFI relay.
PREPARATION:
Remove the EFI relay from the engine room J/B.
CHECK:
Inspect the EFI relay.
OK:
Standard:
Terminal No.ConditionSpecified Condition
3 ± 5Always10 KW or higher
3 ± 5Apply B+ between
terminals 1 and 2Below 1 W
NG Replace EFI relay.
OK
9 Check for open and short in harness and connector between terminal MREL of
ECM and body ground.
PREPARATION:
Disconnect the E4 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tor and body ground.
OK:
Standard:
Tester ConnectionSpecified Condition
MREL (E4±8) ± Body groundBelow 1 W
NG Repair or replace harness or connector.
OK
Check for intermittent problems
(See page DI±11).
Page 701 of 4323
A01995A15196
A15197
IACVIACV closed (VSV: ON)
Intake
Manifold
60°
Throttle valve
opening angle
Engine speed (rpm) 4,700
± DIAGNOSTICSENGINE
DI±499
693 Author: Date:
2005 SEQUOIA (RM1146U)
IACV Control Circuit
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).
When the engine speed is 4,700 rpm or more and the throttle valve opening angle is 60° or more, the VSV
is OFF, so the is IACV open. All the other times, the ECM turns the VSV ON and closes the IACV.
DIDG0±01
Page 702 of 4323
A14809
B
BW
WB 2
EB2V2
VSV (ACIS)
2 1L±W21
E4ECM
ACIS
MREL 13
E3 P±B
B±R 1
1
1
1 1 1 1 1
12 EFI No. 2
EFI Main Relay
21
3
5
EFI No. 1
12
Engine Room No. 1 R/B
B±L
Battery B±W
W±B J3
J/C
AA
D
D
W±B
ECW
FL MAIN
1
1
4B
4A
FL BLOCK J7
J/C
W±B
1A DI±500
± DIAGNOSTICSENGINE
694 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM
Page 703 of 4323
A00307
ON
VSV is ON VSV is OFF
Air Filter Air
Air
E
FE
F
BE6653
FI7073 FI7074
± DIAGNOSTICSENGINE
DI±501
695 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Connect hand±held tester, and check operation of VSV for ACIS.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tes-
ter main switch ON.
(c) Select the ACTIVE TEST mode on the hand±held tester.
CHECK:
Check the operation of the VSV when the VSV is operated by
the hand±held tester.
OK:
VSV is ON:
Air from port E flows out through port F.
VSV is OFF:
Air from port E flows out through the air filter.
OK Check for vacuum tank (See page SF±54).
NG
2 Check VSV for ACIS (See page SF±54).
NG Replace VSV for ACIS.
OK
Page 704 of 4323

A23670
Wire Harness Side
V12
VSV for ACIS connector
B17413
E5E7
E1
ACIS
DI±502
± DIAGNOSTICSENGINE
696 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check for open and short in harness and connector between EFI main relay
(Marking: EFI) and ECM (See page IN±35).
(a) Check the wire harness between the VSV for ACIS and
connector the ECM connector.
(1) Disconnect the VSV for ACIS connector.
(2) Disconnect the E5 and E7 ECM connector.
(3) Check for resistance between the wire harness side
connectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
VSV for ACIS (V12±2) ± ACIS (E5±33)Below 1 W
Standard (Check for short):
Symbols (Terminal No.)Specified condition
VSV for ACIS (V12±2) or ACIS (E5±33) ± E1 (E7±1)10 kW or higher
(b) Check the wire harness between the VSV for ACIS con-
nector and the EFI relay.
(1) Disconnect the VSV for ACIS connector.
(2) Remove the EFI relay from the engine room R/B.
(3) Check for resistance between the wire harness side
connectors.
Standard (Check for open):
Symbols (Terminal No.)Specified condition
VSV for ACIS (V12±1) ± EFI relay terminal 3 of R/BBelow 1 W
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±35).