1996 TOYOTA LAND CRUISER fuel pressure

P09401
−
DIAGNOSTICS ENGINE
DI−11 7
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
TOYOTA hand −held tester
1 Connect the TOYOTA hand −held tester and check operation of fuel pump.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and TOYOTA hand −held tester
main switch ON.
(d) Use ACTIVE TEST mode to operate the fuel pump.
CHECK:
Check for fuel pressure in the fuel return hose when it is pinched
off.
OK:
There is pressure in the fuel return hose.
HINT:
At this time, you will hear a fuel flowing noise.
OK Go to step 4.
NG
2 Check circuit opening relay (See page SF−56 ).
NG Replace circuit opening relay.
OK
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A00194
HighLowFPR
P22900
P09401
DI−120
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
7 Check for open and short in harness and connector between terminal FPR of
ECM connector and fuel pump relay (See page IN−28).
NG Repair or replace harness or connector.
OK
8 Check operation of fuel pump.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(b) Connect the TOYOTA hand − held tester to the DLC3.
(c) Turn ignition switch ON and TOYOTA hand −held tester
main switch ON.
(d) Use ACTIVE TEST mode to operate the fuel pump.
CHECK:
Check operation of fuel pump, when it is operated by the TOYO-
TA hand− held tester and terminal FPR of ECM is grounded and
is not grounded.
OK:
There is pressure in the inlet hose.
HINT:
At this time, you will hear a fuel flowing noise.
FPR is grounded
(Low speed)FPR is not grounded (High speed)
NGNGGo to step 9
NGOKGo to step 10
OKNG
Repair or replace
harness or connector between fuel pump
relay and fuel pump.
9 Check fuel pump (See page SF−6 ).
NG Repair or replace fuel pump.
OK
Check for open or short in harness and connector between EFI main relay (Mark\
ing: EFI) and cir-
cuit opening relay and fuel pump relay and fuel pump and body ground (See p\
age IN−28).
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Version 1.11 - 03/16/2010

A00195
ONFC
BE6653
P22178
P09401
−
DIAGNOSTICS ENGINE
DI−121
1996 LAND CRUISER (RM451U)
10 Check fuel pump resistor. (See page SF−58).
NG Replace fuel pump resistor.
OK
Check for open and short in harness and connector between fuel pump relay and fuel\
pump resis-
tor and fuel pump (See page IN−28).
OBD II scan tool (excluding TOYOTA hand −held tester)
1 Check fuel pump operation.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(b) Turn ignition switch ON.
CHECK:
(a) Connect between terminal FC of ECM and body ground.
(b) Check for fuel pressure in the fuel inlet hose when it is pinched off.
OK:
There is pressure in the fuel inlet hose.
HINT:
At this time, you will hear a fuel flowing noise.
OK Go to step 4.
OK
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Version 1.11 - 03/16/2010

A00196
ONFC
High LowFPR
BE6653
P22901
P09401
−
DIAGNOSTICS ENGINE
DI−123
1996 LAND CRUISER (RM451U)
7 Check operation of fuel pump.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(b) Turn ignition switch ON.
CHECK:
(a) Connect terminal FC of ECM and body ground.
(b) Check operation of fuel pump when terminal FPR of ECM
is grounded and is not grounded.
OK:
There is pressure in the inlet hose.
HINT:
At this time, you will hear a fuel flowing noise.
FPR is grounded
(Low speed)FPR is not grounded (High speed)
NGNGGo to step 8
NGOKGo to step 9
OKNG
Repair or replace
harness or connecter between fuel pump
relay and fuel pump.
8 Check fuel pump (See page SF−6 ).
NG Repair or replace fuel pump.
OK
Check for open or short in harness and connector between EFI main relay (Mark\
ing: EFI) and cir-
cuit opening relay and fuel pump relay and fuel pump and body ground (See p\
age IN−28).
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P22216
Pressure RegulatorVSV
ECM
To Fuel Tank
(Return)
From Delivery Pipe Intake
Manifold
P22482
BRFrom BatteryR/B No.2EB
2
2
2
2
EFI Main
22Y−R
Y−R
EB11
REA27R
R−Y
EZ1
VSV for Fuel21
EZ1
Relay
EFI
12 4
3
1B B3
L−R
Pressure Control E7
E4 3
21 FPU
MRLY
ECM
B+
E01
−
DIAGNOSTICS ENGINE
DI−125
1996 LAND CRUISER (RM451U)
Fuel Pressure Control Circuit
CIRCUIT DESCRIPTION
The ECM turns on a VSV (V acuum Switching Valve) to draw the
air into the diaphragm chamber of the pressure regulator if it de-
tects that the temperature of the engine coolant is too high dur-
ing engine starting.
The air drawn into the chamber increases the fuel pressure to
prevent fuel vapor lock at high engine temperature in order to
help the engine start when it is warm.
Fuel pressure control ends approx. 120 sec. after the engine is
started.
WIRING DIAGRAM
DI5PZ−02
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Version 1.11 - 03/16/2010

A00197
ONON
OFF
BE6653
P22965
P22966
G
E
G E Air Filter
Air Filter
DI−126
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
TOYOTA hand −held tester
1 Connect the TOYOTA hand−held tester and check operation of VSV for fuel
pressure control.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and TOYOTA hand −held tester
main switch ON.
(d) Select the ACTIVE TEST mode on the TOYOTA hand −
held tester.
CHECK:
Check operation of VSV when VSV is operated by the T OYOTA
hand −held tester.
OK:
VSV is ON:
Air from pipe E is flowing out through the air filter.
VSV is OFF:
Air from pipe E is flowing out through pipe G.
OK Check and repair fuel pressure regulator (See page SF−19 ).
NG
2 Check VSV for fuel pressure control (See page SF−59).
NG Replace VSV for fuel pressure control.
OK
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A00198
ONFPU
(+)
(−)
BE6653
P24688
−
DIAGNOSTICS ENGINE
DI−127
1996 LAND CRUISER (RM451U)
3 Check for open and short in harness and connector between EFI main relay
(Marking: EFI) and ECM (See page IN−28).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN−28 ).
OBD II scan tool (excluding TOYOTA hand −held tester)
1 Check VSV for fuel pressure control (See page SF−59 ).
NG Replace VSV for fuel pressure control.
OK
2 Check voltage between terminal FPU of ECM connector and body ground.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminal FPU of ECM connector and
body ground.
OK:
Voltage: 9 − 14 V
NG Check for open and short in harness and con- nector between EFI main relay (Marking: EFI)
and ECM (See page IN−28 ).
OK
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Version 1.11 - 03/16/2010

DI−128
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
3 Check fuel pressure regulator (See page SF−19 ).
NG Repair or replace fuel pressure regulator.
OK
Check and replace ECM (See page IN−28 ).
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010