engine ISUZU TROOPER 1995 Workshop Manual

8-28 CHASSIS ELECTRICAL
DIODE LOCATION
Relay & fuse box
Fuse box
Diode List
Connector X-14
X-15 B-39 8-40 8-43 8-44
B-45 8-46 No.
~
Corner-Dome Li-Anti-Anti-theft
Mode Cruise ing ECM ghtAnti-
theft Light
switch control EBCM
light
theft remind RWAL
DOHC 0
0 0 0
0 0 0 0
SOHC 0
0 0 -0 -0 -
ECM:
Engine Control Module, TCM: Transmission Control Module1
A/C: Air Conditioning, RWAL: Rear Wheel Anti-Lock, EBCM; Electronic Brake Control Module
Fig. 8-47
•

GROUNDING POINT
REFERENCE TABLE
Connector No.
Cable harness
~
~
I B-1a1
Body harness
I B-191
I B-261
1 lc-16 I
2IC-16 I
3IC-16 I
4IC-16 I
Engine room
5IC-16 I
harness
6IC-16 I
7IC-16 I
aiC-16 1
Location
Body-RH
Body-LH
Body-center
Fender-LH
CHASSIS ElECTRICAL 8-29
Parts (Load)
Remind buzzer, Key remind switch (Starter
switch),
Sun roof control unit, Sun roof motor, Sun roof switch, Safety stop switch, Limit
switch
Door lock key switch (Front-RH), Cruise control
unit, Cigar lighter, Door mirror (RH), Front door
key switch (RH), Front door lock actuator (RH),
Fan switch, Starter relay, Front
door lock & power window switch (LH, RH), Front power window motor
Door lock key switch (Front-LH), Front power window motor (LH), Door mirror (LH), Front
door key switch (LH), Front door lock actuator
(LH), Rear wiper intermittent relay, Front door
lock & power window switch (LH)
Starter relay, Headlight
wiper switch,
Anti-theft controller,
Dimmer·passing switch, Fog light switch, Headlight, Lighting
relay, Fog
light relay, Illumination controller,
Illumination light, Rear defogger switch, Rear
defogger relay, Flasher unit,
Power window relay, Cruise control main relay, Kick-down
switch, Audio, Intermittent relay (front), Mode SW, Tail relay, Lighting SW, Cornering light
relay, Glove box switch, Digital clock,
Transmission control module, Heater & A/C
relay, Front
door key switch, Door mirror
control switch, Door mirror folding switch,
Door mirror defogger switch, Meter assembly
Seat heater, Seat heater switch, Fuel pump, Fuel pump relay, Seat belt switch, Remind
buzzer, Power and winter switch, Shift lock
controller, Rear
door lock actuator, Fuel tank
unit, Power seat SW, Front tilt motor & switch,
Rear tilt motor & switch, Slide motor, Recliner
motor & switch, Rear power window switch
(LH, RH), Rear power window motor (LH, RH),
Seat belt warning light
Headlight
wiper motor
Power steering pressure SW
4WD switch, 4WD indicator (meter), Brake fluid
SW, Oxygen sensor (M/T)
Electronic brake control
module
Front side marker light (LH, RH), Cornering
light, Cornering light switch (Combination
switch), Front turn signal light, Turn signal light switch (Combination switch), Parking light (LH, RH)
Fog light, Fog light relay
Hydraulic
unit
Oxygen sensor (AfT), ABS & Upshift relay,
Transmission SW

8-30 CHASSIS ELECTRICAL
Connector No.
Cable harness
Location Parts (load)
1jC-39I Windshield washer motor
21 C-391 Upshift-1 relay, Intermittent relay (Front)
31 C-391 Windshield wiper motor
41 C-39j Vehicle speed
sensor, Hazard warning switch,
Turn
signal indicator (Meter), Meter assembly
sl C-391 Fender-RH Headlight wiper timer, Headlight washer motor
Engine room
harness Engine Control Module (ECM)
main relay, Fuel
71 C-391 pump relay, Cruise control main relay, Cruise
control main switch, Air Conditioning relay,
Lockup off relay, Upshift-2 relay, Transmission-
1, 2 switch
al C-391 Vacuum pump and vacuum switching valve
I C-451 Rear wheel anti-lock controller
sl c-asl
Body-FRT Electronic brake control module, Data link
connector
I C-961 Front end Rear wheel
anti-lock valve
I E-281 Knock sEmsor module (DOHC), ECM, Oxygen
Common sensor (SOHC)
I E-291 chamber Knock sensor (DOHC), ECM, Oxygen sensor
(DOHC)
Engine
ECGI
I E-30 I harness Duct (DOHC) Ignition control
module
Common chamber
ECM, AfT Shift indicator control unit, Data link
I
E-311 (SOHC) connector, Knock sensor (DOHC)
~ Chassis harness Frame
Rear wheel anti-lock valve
11-391 Instrument
harness
Body-FRT Audio
IM-161 Transmission
Engine Transmission control module harness
Rear defogger
relay, Rear defogger, Tailgate
~
key switch, Tailgate lock actuator, Rear washer
motor, A:ear wiper and washer switch, Rear
wiper motor, Stoplight switch, Brake switch,
High
mount stoplight
Rear body Body-RR
harness Taillight, Stoplight, Stoplight switch, Brake
switch,
near turn signal light, Backup light,
~
Backup light switch, Mode switch, License plate
light, Lu!;)gage room light, Trailer harness con-
nector
(Stoplight, taillight), License plate light
~ DERM
00 SRS harness Body-FRT
DERM, Forward sensor, Inflator module (Driver
& passenger),
SRS coil assembly
•

::!! cc 00 I U1 N
(
I RR
DOOR
HARNESS
(RH)
I

I DOMEUGHTHARNESSJ
.--------------

I FRT
DOOR
HARNESS
(RH)
I

ENGINE
ROOM
HAR~NESS
~:~i 16
RELAY
& FUSE
BOX
20
(FL-1,
FL-2,
FL-3,
FL-6,
F ) -------------"-
~/ /
BATTERY"------,//
"
\_
(
TAILGATE
HARNESS
(RH)
\,
TAILGATE
HARNESS
(LH)
R-3 R-4
RR
DOOR
HARNESS
ILHl
FRT
DOOR
HARNESS
(LH)

H-22 H-23 H-24
BODY
HARNESS
FUSE
BOX
(C-1
-C-241
ENGINE
ROOM
HARNESS
(
0 :1: )> fJ)
fJ) Ci) m r­m 0 -4 ::0 n )> r-eo I w (J1

STARTER SWITCH (FIG. 8-59)
Fig. 8-58
~
~
LOCK Removed
OFF
ACC Inserted
ON
START
4
(62)
CHASSIS ELECTRICAL 8-43
The starter switch positions are LOCK, OFF, ACC, ON
and START. Turning the starter key to these positions
provides a circuit
for starting the engine, the opera­
tion of accessories, or stops the engine.
~ INSPECTION
1 ~ 1 Check the continuity between the starter switch
connector terminals. (Fig. 8-59)
1
Repair or replace the switch when the result of
inspection is found abnormal.
5 3 2 7 8 6
(ACCl (IG2l (STl (61) (IG1l (KEY(£)) (KEY8l
o----o
Fig.
8-59

8-44 CHASSIS ELECTRICAL
B REMOVAL (FIG. 8-60)
Preparation: Disconnect the battery ground cable.
5. Starter switch
Fig. 8-60
1. Front console assembly
• Remove four screws.
• Remove the transmission shift lever knob.
• Remove the transfer shift lever knob.
• Disconnect the seat heater switch connectors
(If so equipped).
• Disconnect the "POWER & WINTER" switch
connectors
(A/T only).
2. Lower cluster assembly
• Remove three screws.
• Disconnect the cigar lighter connectors.
• Remove the cigar lighter illumination bulb
socket.
• Disconnect the ashtray illumination bulb
connector.
3. Instrument panel driver lower cover
• Remove the engine hood opener.
• Remove three screws and clip.
• Disconnect four fasteners.
4. Steering cowl
• Remove seven screws .
5. Starter switch
• Disconnect the connector.
• Remove the screw.
B INSTALLATION
To install, follow the removal steps in the everse
order noting the
following point.
1. When installing the steering cowl, be sure o pass
the harnesses through the route as
show in the
illustration so that the starter switch, th com­
bination switch and the inflator
module
will not get caught. (Fig. 8-61)
Starter switch
harness
Fig. 8-61
CLUTCH START SWITCH
cowl
When the clutch pedal is depressed, the clute start
switch is turned on
to form a circuit to activ e the
starter.
~ INSPECTION
1 til!. I Check the continuity between the clute start
switch terminals. (Fig. 8-62)
Replace the switch when the result
of insp ction
is found abnormal.

'

CHASSIS ELECTRICAL 8-47
ENGINE CONTROL MODULE (ECM)
GENERAL DESCRIPTION
The ECM is used to control the fuel system of the
vehicle, especially in controlling the following items.
1. FUEL CONTROL
The amount of fuel and air sent into the combus­
tion chamber is controlled by controlling the fuel
sent through the injector.
2. ELECTRIC FUEL PUMP (INSTALLED IN
THE FUEL TANK)
The in-tank fuel pump is controlled by the ECM.
When starter switch is turned on, the pump will
run for 2 seconds, then stop unless the engine is
cranking
or running.
3. IGNITION CONTROL
The system is controlled by the spark timing con­
trol function of the ECM.
4. CIRCULATION OF EXHAUST GAS
The system controls the formation of NOx by
returning a small amount of exhaust gas to the
intake manifold
through the control valve.
'-" lAC: Idle air control
5. CONTROL OF AIR CONDITIONING (A/C)
For improved engine idling performance, the sys­
tem controls the operation of the air conditioner
by regulating the
clutch operation ofthe A/C com­
pressor in accordance
with changes in operation.
6. IDLE AIR CONTROL
The system controls the lAC Valve for the desired
idle speed in accordance
with changes in
operation.
7. DIAGNOSIS OF TROUBLES
When a sensor detects any signal that the ECM is
in
an abnormal condition, the ECM turns on the
malfunction
indicator (CHECK ENGINE) light in
the meter, and stores at the same
time the corre­
sponding diagnostic
trouble code (DTC) in the
memory to indicate to which system or circuit the
trouble represented by the
DTC belongs.
The ECM inspection connector (data link connec­
tor) is used
to retrieve the DTCs stored from the
ECM.
Refer to Section 6 "ENGINE DIAGNOSIS" for de­
tails.

.~·-
, ca· CIO I O'l O'l
ENGINE
COOLANT TEMPERATURE SENSOR
VSV:
INTAKE
AIR~""-"-,
FUEL
~,
'"-
E-22
INJECTOR
No.5
'~~
FUEL
~
"':·.E-23
INJECTOR
No.3
"-
'"<
FUEL
"-
·,,,
E-~
4 /'
INJECTOR
No.'1'~-
1~4 "...

.......
. .......
' '
/
BODY
ASM
"-..'-
>
DIS / / E-18
ICM !POWER)
THROTILE '
E-~5·.-..,
.. '-, ·,/
r
E-2~,,
/E-5v~~;>o~~
--vsv:EGR
FUEL
INJECTOR
No.6
E-11
~E-10 ~FUEL
INJECTOR
No.4
E-27-+
"'
:1
~
.........
_
'-......
"·INTAKE
AIR TEMPERATURE SENSOR
ECM EGR EVAP
lAC
ICM MAP TP vsv )
X
·"
~
FUEL
INJECTOR
No.2
VSV: EVAP CANISTER
E28
E29
RESISTOR:UPSHIFT-M/T

CRANKSHAFT
POSITION
SENSOR
MAP
SENSOR RELAY:UPSHIFT-M/T ,
ENGINE
CONTROL
MODULE
EXHAUST GAS RECIRCULATION
EVAPORATIVE EMISSION IDLE
AIR CONTROL
IGNITION CONTROL
MODULE
MANIFOLD ABSOLUTE PRESSURE
THROTILE POSITION VACUUM
SWITCHING
VALVE
DIODE-AfT
'...,
RELAY:
ECM
MAIN
~"'-.,'...,
RELAY:FUEL
PUMP
'....
'
RELAY
& FUSE BOX
(FL-1,FL-2,FL-3,F-2,F-10)
BATIERY~
H-41 H-42~
KNOCK SENSOR
MODULE
)
DATA
LINK
CONNECTOR
VEHICLE
SPEED
SENSOR
(METER)
MALFUNCTION INDICATOR LIGHT (CHECK ENGINE) UPSHIFT INDICATOR LIGHT
(METER)-M/T
STARTER
SW
·~FUEL
PUMP
EVAP CANISTER
)
~
co I
~
~ co
(/)
0
r-
:::t
0
)> C/)
0
C/)
~
Cii
-
m
0
r-m
2
0
I
~
c
:a
0
0 )>
J:
r-
0

!! (Q
(
FUEL INJECTOR
No.1
/
FUEL INJECTOR
No.5
FUEL INJECTOR
No.3
I
\/.
ICM
CPOWERl
_/
E-27
cp
I
CRANKSHAFT
~
POSITION SENSOR
ECM
: ENGINE
CONTROL
MODULE
EGR
:EXHAUST
GAS
RECIRCULATION
lAC
: IDLE
AIR
CONTROL
ICM
: IGNmON
CONTROL
MODULE
MAP
: MAN
I FORD
ABSOLUTE
PRESSURE
VSV
:VACUUM
SWITCHING
VALVE
(
VSV:EGR I VSV:
EVAPORATIVE
EMISSION
CANISTER
THROTTLE
POSmON
SENSOR
~FUEL
INJECTOR
No.6
FUEL
INJECTOR
No.4
FUEL
INJECTOR
No.2
ICMCCRl ICMCCONTl
RESISTOR:UPSHIFT-MIT RELAY:UPSHIFT-1-MIT
DIODECAITl
RELAY:
ECM
MAIN
RELAY:FUEL
PUMP
RELAY
& FUSE
BOX
CFL-1,FL-2,FL-3,F-2,F-10l
H-41 H-42
POWER
STEERING
PRESSURE
SW.
H-33
VEHICLE
SPEED
SENSOR (METER) MALFUNCTION INDICATOR
LIGHT
(CHECK
ENGINE)
UPSHIFT
INDICATOR
LIGHT
CMETERl-MfT
(
/STARTER
SW.
F-4
/
DATA
LINK
I
d .
'v_AR__
FUEL
PUMP
CONNECTOR~
!P
~;~·
/~
,,
1-9
~ ~ r-0 n ~ 0 2 • en 0 X n
(") ::::1: )> CJ)
CJ) Cii m r­m ~ :D ~ r-01) I fD

w " ~~ O.SLJY ~ ..
2"' a~ u$ ~f~ ~~ ~g~
FENDER-RH II
DUCT II
~~~~~II
DUCT II
INTAKE AIR TEMPERATURE SENSOR
~~ 0~
a; d
0.89
C-1 A&
THROTTLE POSITION
SENSOR
... 5! ., .. ::> 0: ~
m
0.85LIO
~ a d d
li~Ui"o:i UOlUCJI> i;i;i:b ~wuw "'"" ~ ~ g g
"' il " Ill
13
§
; w 0 0: .. 5N ~;:; 8<:1 d~ u"' ~~ ~~ ~~ z< ., .. ~g ~g
~ § :;1 ~ d
0: " Ill d
ENGINE COOLANT
TEMPERATURE
SENSOR
CHASSIS ELECTRICAL 8-51
~ ~ ~w _.,
i£ ~g
~ i ;zf d
d
IIi ~ d .. :b
~~ ~g
~
"' ~ 5I d "'
13 12 H-6 H-6
.. ~ "' ~ il il
!
! ! ~
~ ~ I ~ CD ! ! ~
i
i
TCM: TRANSMISSION CONTROL MODULE, A/C: AIR CONDITIONING