Page 2793 of 4770
± DIAGNOSTICSENGINE (1MZ±FE)
DI±373
608 Author: Date:
9 Check for open and short in harness and connector between terminal MREL of
ECM and body ground (See page IN±31).
NG Repair or harness or connector.
OK
Check and repair harness or connector be-
tween EFI No.1 fuse and battery
(See page IN±31).
Page 2794 of 4770
A07151
Fuel Pump Circuit Opening Relay
EFI Main Relay
FC
Tr
MREL
IGSW
STA EFI
NEECM
Starter Starter Relay MAIN
Battery AM2IG Switch
(NE Signal) (STA Signal) Park/ Neutral Position Switch IGN
STARTER DI±374
± DIAGNOSTICSENGINE (1MZ±FE)
609 Author: Date:
Fuel Pump Control Circuit
CIRCUIT DESCRIPTION
In the diagram below, when the engine is cranked, current flows from terminal ST of the ignition switch to
the starter relay coil and also current flows to terminal STA of ECM (STA signal).
When the STA signal and NE signal are input to the ECM, Tr is turned ON, current flows to coil of the circuit
opening relay, the relay switches on, power is supplied to the fuel pump and the fuel pump operates.
While the NE signal is generated (engine running), the ECM keeps Tr ON (circuit opening relay ON) and the
fuel pump also keeps operating.
DI4DV±01
Page 2795 of 4770
A07451
ECM
E01 FC 3
E7
G±R
5EB1
G±R 1
1
1 1 15
3
2
CIR OPN Relay
Engine Room R/B
L±B
EB1
ID1L±B
A
A
5 4 10
7
W±B
W±BJ11
Junction
Connector
IG BL
StarterS2
B±R
EB
B±R 2D
2K 2F
9 5 4 2C 10
II2
10
Junction
Connector
J8 J7
C B(A/T)
(A/T) GR
(M/T) B±WPark/
Nutral
Position
Switch
6 5(A/T)
B±W(A/T)
B±WII2
11 11
ST Relay
B B
B EFI Relay23
15
2
13 5
2J 2K
W±BB±R W±B B±RB±W
7 8R1K
W±R
1J
43
1B
STARTER
5 5
1
2 B±W
W±B
2A
2B31
2L 4 AM27Instrument Panel J/B
Battery
B±GFL
MAIN F6
F4 1
Fusible
Link
BlockB B
EFI
MAINB+
MREL
8
E7
B±R
Fuel
Pump
1W 1K1
IGN
1
ST2
IG2
AM2Clutch
Start
Switch
L±BW±B
Junction
Connector
A
J40
Junction
Connector
1K 7
*B±O *1GR
(M/T)
*B±O *1GR
J35 J35C
*B±O *1GR
B±W
B±R
Junction
Connector J26
1
7
3
1K
*: TMMK made
*
1: TMC made
± DIAGNOSTICSENGINE (1MZ±FE)
DI±375
610 Author: Date:
WIRING DIAGRAM
Page 2796 of 4770
A00244
ON
BE6653
P20186
DI±376
± DIAGNOSTICSENGINE (1MZ±FE)
611 Author: Date:
INSPECTION PROCEDURE
TOYOTA hand±held tester
1 Connect TOYOTA hand±held tester and check operation of fuel pump.
PREPARATION:
(a) Connect the TOYOTA hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand±
held tester main switch ON.
(c) Use ACTIVE TEST mode to operate the fuel pump.
CHECK:
Check that pulsation damper screw rises up when fuel pump is
on by TOYOTA hand±held tester.
OK:
The pulsation damper screw rises up.
OK Check for starter signal circuit
( See page DI±384).
NG
2 Check for ECM power source circuit (See page DI±369).
NG Repair or replace.
OK
3 Check circuit opening relay (See page SF±54).
NG Replace circuit opening relay.
OK
Page 2797 of 4770
A02064
ON
FC (+)
± DIAGNOSTICSENGINE (1MZ±FE)
DI±377
612 Author: Date:
4 Check voltage between terminal FC of ECM and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF±73).
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminal FC of ECM and body
ground.
OK:
Voltage 9 ± 14 V
NG Check for open in harness and connector be-
tween EFI main relay (Marking: EFI) and circuit
opening relay, circuit opening relay and ECM.
OK
5 Check fuel pump (See page SF±6).
NG Repair or replace fuel pump.
OK
6 Check for open in harness and connector between circuit opening relay
and fuel pump, and fuel pump and body ground
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).
Page 2798 of 4770
A02042
ON
FC
DI±378
± DIAGNOSTICSENGINE (1MZ±FE)
613 Author: Date:
OBD II scan tool (excluding TOYOTA hand±held tester)
1 Check operation of fuel pump.
PREPARATION:
(a) Remove the glove compartment (See page SF±73).
(b) Turn the ignition switch ON.
CHECK:
(a) Connect between terminal FC of the ECM connector and
body ground.
(b) Check that pulsation damper screw rises up when con-
nect between terminal FC of the ECM and body ground.
OK:
The pulsation damper screw rises up.
OK Check for starter signal circuit
( See page DI±384).
NG
2 Check for ECM power source circuit (See page DI±369).
NG Repair or replace.
OK
3 Check circuit opening relay (See page SF±54).
NG Replace circuit opening relay.
OK
Page 2799 of 4770
A02064
ON
FC (+)
± DIAGNOSTICSENGINE (1MZ±FE)
DI±379
614 Author: Date:
4 Check voltage between terminal FC of ECM and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF±73).
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminal FC of ECM and body
ground.
OK:
Voltage 9 ± 14 V
NG Check for open in harness and connector be-
tween EFI main relay (Marking: EFI) and circuit
opening relay, circuit opening relay and ECM.
OK
5 Check fuel pump (See page SF±6).
NG Repair or replace fuel pump.
OK
6 Check for open in harness and connector between circuit opening relay and fuel
pump, and fuel pump and body ground (See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN±31).
Page 2800 of 4770
A00306
135
24 6 IACVIACV closed (VSV: ON)
Throttle Valve30°
3,700 rpm
Engine speed
Throttle valve
opening angle
FI7011 FI6570
A07452
From Battery 2J2
W±B
B±Y
J20
Junction
Connector 9
AAECMACIS
12
MRELB±W
VSV for ACIS
R±Y B±Y 17
2K
2A 2F
51 2
3 4Engine Room J/B
EFI
EBJunction
Connector BB+
B±Y178
E11E7
B
B±YE01
B±W
J36 J35CC
EFI Relay
J27 J28
II3Junction Connector DI±380
± DIAGNOSTICSENGINE (1MZ±FE)
615 Author: Date:
IACV Control VSV Circuit
CIRCUIT DESCRIPTION
This circuit opens and closes the IACV (Intake Air Control Valve) in response to the engine load in order to
increase the intake efficiency (ACIS: Acoustic Control Induction System).
When the engine speed is 3,700 rpm or less and the throttle valve opening angle is 60° or more, the ECM
turns the VSV ON and closes the IACV. At all other times, the VSV is OFF, so the IACV is open.
WIRING DIAGRAM
DI08E±06