Page 450 of 2062
Downloaded from www.Manualslib.com manuals search engine BE6653
P24320
P24319A00111
ON
#10 #20
#30#40 #50 #60 (+) (+) (+) (+) (+)
(+)
#10 #20 #40 #50 #60#30(+) (+) (+) (+) (+) (+)
For M/T
For A/T
DI−186
− DIAGNOSTICSENGINE (5VZ−FE)
1996 TOYOTA T100 (RM449U)
2 Check voltage of ECM terminal for injector of failed cylinder.
PREPARATION:
(a) Remove the right cowl side trim (See page SF−61).
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between applicable terminal of ECM connec-
tor and body ground.
OK:
Voltage: 9 − 14 V
OK Go to step 4.
NG
3 Check resistance of injector of misfiring cylinder (See page SF−21).
NG Replace injector.
OK
Check for open and short in harness and con-
nector between injector and ECM (See page
IN−26).
4 Check fuel pressure (See page SF−5).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF−5).
OK
Page 519 of 2062

Downloaded from www.Manualslib.com manuals search engine A01010
EFI
AM2
AM1
ALT
BatteryIG Switch
IG2
IG1
STIGNEFI Relay
Circuit Opening Relay
Clutch Start
Cancel Switch
(M/T)
L1 L2
ECM Fuel Pump
FC
Tr
STA
NE
Starter
Park/Neutral
Position Switch
(A/T)
Relay Starter
Start Clutch
Switch
(M/T)Crankshaft From
Position
Sensor(STA Signal)
(NE Signal)
− DIAGNOSTICSENGINE (5VZ−FE)
DI−255
1996 TOYOTA T100 (RM449U)
Fuel Pump Control Circuit
CIRCUIT DESCRIPTION
The fuel pump is switched on (low voltage at terminal FC) when STA is on or while the NE signal is input to
the ECM.
In the diagram below, when the engine is cranked, current flows from terminal ST of the ignition switch to
the starter relay coil, the starter relay switches on and current flows to coil L1 of the circuit opening relay.
Thus the circuit opening relay switches on, power is supplied to the fuel pump and the fuel pump operates.
When the STA signal and NE signal are input to the ECM, Tr is turned ON, current flows to coil L2 of the circuit
opening relay, the relay switches on 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.
DI0VC−01
Page 520 of 2062
Downloaded from www.Manualslib.com manuals search engine A00651
ECM
EFI AM2 ALT
Battery
IG Switch
Park/
Switch
StarterOpening Relay
Clutch
Start
Switch
E01 FC 4 14
E7 E5
(M/T)(A/T)
G−Y13
IE1 G−YL
1 4
6
Circuit
8
W−B
BJ1
W−B
IC
IC2 W−RW−R
EA19
EA
6
B−WB−R
Relay
(M/T)
3
B−O
WB−W
3
2
22
2 RelayEFI
2 22
51
2
22
2
22 5 R/B
1 2 2
2 3
1 W
W
B−YIA3
IGN
B (M/T)
B
Neutral
Position
(A/T)
Fuel
PumpW−BBJ1 BJ2
BJ2W−B(w/ ABS)
(w/o ABS)
11
(w/ ABS)
(w/o ABS)
10 16
Clutch
Start
Switch
(M/T)Cancel
No.2Starter
J/B No.1
B−R
B−WB−W
B−W B−W
B−W
B−O
B
B−R
W−B
W−RW
B−Y
W 2
2W−B
AM1
23
151 5
1 36 873 17 1113
IC
EB1
S1
EA1IA3
IA31C1A
1
IE1
IE1
B−Y
W−R
W−B
2
2 5 6 4
1
13A/T
DI−256
− DIAGNOSTICSENGINE (5VZ−FE)
1996 TOYOTA T100 (RM449U)
WIRING DIAGRAM
Page 521 of 2062
Downloaded from www.Manualslib.com manuals search engine BE6653A00773A00788Fuel Inlet Hose
ON
− DIAGNOSTICSENGINE (5VZ−FE)
DI−257
1996 TOYOTA T100 (RM449U)
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 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 7.
NG
2 Check for ECM power source circuit (See page DI−244).
NG Repair or replace.
OK
Page 523 of 2062
Downloaded from www.Manualslib.com manuals search engine A00686
1 2
34
6
3 (+)
6 (−)1
2
− DIAGNOSTICSENGINE (5VZ−FE)
DI−259
1996 TOYOTA T100 (RM449U)
5 Check fuel pump (See page SF−5).
NG Repair or replace fuel pump.
OK
6 Check for open in harness and connector between circuit opening relay and fuel
pump, fuel pump and body ground (See page IN−26).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN−26).
7 Check circuit opening relay.
PREPARATION:
Remove the circuit opening relay (See page SF−46).
CHECK:
(a) Apply battery voltage between terminals 3 and 6.
(b) Check continuity between terminal 1 and 2.
OK:
Continuity
NG Replace circuit opening relay.
OK
Page 524 of 2062

Downloaded from www.Manualslib.com manuals search engine A00687
START3
BE6653P24337P24336
A00773A00789
ON
For M/T
For A/TFC (+)
FC (+)
Fuel Inlet Hose
DI−260
− DIAGNOSTICSENGINE (5VZ−FE)
1996 TOYOTA T100 (RM449U)
8 Check voltage between terminal 3 of circuit opening relay connector and body
ground.
CHECK:
Measure voltage between terminal 3 of circuit opening relay
connector and body ground when engine is cranked.
OK:
Voltage: 9 − 14 V
NG Check for starter signal circuit (See page
DI−248).
OK
Check for open in harness and connector be-
tween terminal 6 of circuit opening relay con-
nector and body ground (See page IN−26).
OBD II scan tool (excluding TOYOTA hand−held tester):
1 Check operation of fuel pump.
PREPARATION:
(a) Remove the right cowl side trim (See page SF−61).
(b) Turn the ignition switch ON.
CHECK:
(a) Connect between terminal FC of ECM connector and
body ground.
(b) Check for fuel pressure in the 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 7.
NG
Page 525 of 2062
Downloaded from www.Manualslib.com manuals search engine − DIAGNOSTICSENGINE (5VZ−FE)
DI−261
1996 TOYOTA T100 (RM449U)
2 Check for ECM power source circuit (See page DI−251).
NG Repair or replace.
OK
3 Check circuit opening relay (See page DI−255, step 3).
NG Replace circuit opening relay.
OK
4 Check voltage between terminal FC of ECM connector and body ground (See
page DI−255, step 4).
NG Check for open in harness and connector be-
tween EFI main relay and circuit opening relay
and ECM (See page IN−26).
OK
5 Check fuel pump (See page SF−5).
NG Repair or replace fuel pump.
OK
Page 526 of 2062
Downloaded from www.Manualslib.com manuals search engine DI−262
− DIAGNOSTICSENGINE (5VZ−FE)
1996 TOYOTA T100 (RM449U)
6 Check for open in harness and connector between circuit opening relay and fuel
pump, fuel pump and body ground (See page IN−26).
NG Repair or replace harness or connector.
OK
Check and replace ECM (See page IN−26).
7 Check circuit opening relay (See page DI−255, step 7).
NG Replace circuit opening relay.
OK
8 Check voltage between terminal 3 of circuit opening relay connector and body
ground (See page DI−255, step 8).
NG Check for starter signal circuit (See page
DI−248).
OK
Check for open in harness and connector be-
tween terminal 6 of circuit opening relay con-
nector and body ground (See page IN−26).