MITSUBISHI MONTERO 2000 Service Repair Manual

GDI -Troubleshooting <A/T>13A-187
Inspection procedure 20
Idling speed is improper when A/C is operating (A/C
switch 2 signal)
Probable cause
The A/C-ECU judges ifloadcaused by air conditioner ishigh or low, and
converts it to A/C switch 2 signal to send the engine-A/T-ECU it.
Based on this signal, the engine-A/T-ECU operates the throttle control servo to
control the idle-up speed.DMalfunction of the A/C control system
DOpen or short circuit, or loose connector contact
DMalfunction of the engine-A/T-ECU
OK
Check the trouble symptoms.
Check the harness wire between the engine-A/T-ECU and the
A/C-ECU.OKCheck the A/C system
(Refer to GROUP 55 - Troubleshooting.)
NGNG
RepairOK
Replace the engine-A/T-ECU.
Check the following connectors:
D-120, D-131, E-13
RepairNG
Inspection procedure 21
A/C condenser fan is inoperative
Probable cause
The fan motor relay is controlled by turning on and off the power transistor in
the engine-A/T-ECU.DMalfunction of the A/C condenser fan relay.
DMalfunction of the A/C condenser fan motor.
DOpen or short circuit, or loose connector contact
DMalfunction of the engine-A/T-ECU
NG
Replace the engine-A/T-ECU. OK
NG
RepairOK
Check the trouble symptoms.
Check the following connector:
D-119
Measure at the engine-A/T-ECU connector D-119.
DDisconnect the connector, and measure at the harness
side.
DCheck condition of the condenser fan.
(Ignition switch: ON)
OK:
Fan stops.
DThe voltage between terminal 18 and earth
(Ignition switch: ON)
OK:
System voltage
DConnect terminal 18 to earth.
(Ignition switch: ON)
OK:
A/C condenser fan rotates.NGCheck the condenser fan circuit. (Refer to ELECTRICAL
WIRING.)


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-188
Inspection procedure 22
GDI ECO indicator lamp does not illuminate.
Probable cause
If the GDI ECO indicator lampdoes notilluminate after turningswitch, the causes
listed in the right column are suspected.DBurned-out GDI ECO indicator lamp bulb
DOpen circuit or short-circuited harness wire in the GDI
ECO indicator lampcircuit
DMalfunction of the engine-A/T-ECU
DMalfunction of the GDI ECO indicator lamp ECU
NG
Repair
Measure at the engine-A/T-ECU connector D-119.
DDisconnect the connector, and measure at the harness side.
DEarth terminal 14 (Ignition switch: ON)
OK:
The GDI ECO indicator lamp illuminates.OKCheck the following connector:
D-119
OK
Check trouble symptom.
NG
Replace the engine-A/T-ECU.
NG
Check the following connectors:
E-13, E-112
Check trouble symptom.
Check the harness wire between the GDI ECO indicatorlamp
ECU and engine-A/T-ECU.
Check the relative circuit of GDI ECO indicatorlamp.(Refer to
GROUP 54A - Troubleshooting.)NG OK
OK NG
NG
Repair
Repair
Inspection procedure 23
GDI ECO indicator lamp remains illuminated and does
not go off.
Probable cause
If the GDI ECO indicator lampdoes not go off duringhigh load operation, thecauses
listed in the right column are suspected.DShort circuit between the GDI ECO indicatorlamp and
engine-A/T-ECU
DMalfunction of the engine-A/T-ECU
DMalfunction of the GDI ECO indicator lamp ECU
OK
Replace the engine-A/T-ECU.
Measure at GDI ECO indicator lamp ECUconnector E-112.
DDisconnect the connector, and measure at the harness side.
DDisconnect the engine-A/T-ECU connector.
DContinuity between terminal 3 and earth
OK:
No continuityNGCheck the harness wire between the GDI ECO indicatorlamp
ECU and engine-A/T-ECU, and repair if necessary.
OK
Check the relative circuit of GDI ECO indicatorlamp.(Refer to
GROUP 54A - Troubleshooting.)


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-189
Inspection procedure 24
Engine-A/T-ECU power supply and earth circuit system
Probable cause
The cause is probably the malfunction of the engine-A/T-ECU, or the
malfunctions listed at right.DOpen circuit or short-circuited harness wire in the
engine-A/T-ECU power supply circuit.
DOpen circuit or short-circuited harness wire to
earth in the engine-A/T-ECU.
DMalfunction of the engine-A/T-ECU
OK(5) NG
OK
Check the trouble symptoms.
NG
Repair
(2), (3) NG
Check the harness wire between the
engine-A/T-ECU and the battery, and
repair if necessary.
OK
Check the trouble symptoms.
OK
NG
Check the harness wire between the
engine-A/T-ECU and the ignition
switch.
Ignition switch check
(Refer to GROUP 54 - Ignition
Switch.)
(4) NG
Measure at engine-A/T-ECU
connectors D-120, D-121.
DDisconnect the connector, and
measure at the harness side.
(1) The voltage between terminal 98
and earth.
(Ignition switch: ON)
OK:
System voltage
(2) The voltage between terminal 49
and earth.
OK:
System voltage
(3) The voltage between terminals 41
and 47 and earth.
(Ignition switch: ON)
OK:
System voltage
(When terminal 49 was
connected to earth)
(4) The continuity between terminals
42 and 48 and earth.
OK:
Continuity
(5) The voltage between terminal 66
and earth
OK:
System voltage(1) NGCheck the following connectors:
D-208, D-223 <LHD>, E-13NG
Repair
OK
Check the following connectors:
D-120, D-121
NG
Replace the engine-A/T-ECU.
OK
Check the trouble symptoms.Repair NG
NG
RepairCheck the following connectors:
D-27, D-31 <LHD>, D-223 <LHD>,
E-13
NG
Check the following connector:
D-128Repair NG
Check the trouble symptoms.
NG
Check the harness wire between the
engine-A/T-ECU and theengine
control relay, and repair if necessary.
OK
Check the following connector:
D-14Repair NG
Check the trouble symptoms.
NG
Check the harness wire between the
engine-A/T-ECU and earth, and
repair if necessary.


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-190
Inspection procedure 25
Engine control relay, ignition switch-IG system
Probable cause
When an ignition switch ON signal is input to the engine-A/T-ECU, the
engine-A/T-ECU turns the control relay ON.
This causes system voltage to be supplied to the engine-A/T-ECU, sensors, and
actuators.DMalfunction of the ignition switch
DMalfunction of the control relay.
DOpen circuit or short-circuited harness wire in the
engine controlrelay circuit.
DMalfunction of the engine-A/T-ECU
Check the harness wire between the
battery and theengine controlrelay,
and repair if necessary.
Check the engine-A/T-ECU power
supply and earth circuit. (Refer to
P.13A-189, Inspection procedure 24.)OK
OK
Measure at control relay connector
B-25X.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between 2, 3 and
earth
OK:
System voltageNG
Check the control relay.
(Refer to P.13A-227.)NG
Replace
Inspection procedure 26
Injector driver relay system
Probable cause
When an ignition switch ON signal is input to the engine-A/T-ECU, the
engine-A/T-ECU turns the injector driver relay ON.
This causes system voltage to be supplied to the injector driver.DMalfunction of the injector driver relay.
DOpen or short circuit, or loose connector contact
DMalfunction of the engine-A/T-ECU
OK
Check the trouble symptoms.
OK
Check the trouble symptoms.
OK
Check the trouble symptoms.
Check the injector driver relay (Refer to P.13A-227.)NG
Replace
OK
(1) NG
Check the harness wire between the injector driver relay and
the battery, and repair if necessary.
(2)NG
Check the following connectors:
D-208, D-223 <LHD>, E-13
OK
Check the trouble symptoms.
NG
Check the harness wire between the injector driver relay and
the ignition switch, and repair if necessary.
OK
Measure at engine-A/T-ECU connector D-119.
DDisconnect the connector, and measure at the harness
side.
DThe voltage between terminal 6 and earth (Ignition switch:
ON)
OK:
System voltageNGCheck the following connector:
B-28X
NG
Check the harness wire between the injector driver relay and
the engine-A/T-ECU, and repair if necessary.
OK
Check the following connector:
D-119
NG
Measure at injector driver connector B-121.
DConnect the connector.
DThe voltage between terminal 4, 12, 21 and earth
(Ignition switch: ON)
OK:
System voltageNGCheck the following connector:
B-28X
OK
Check the injector driver system.
(Refer to P.13A-196, Inspection procedure 34.)
NG
Check the harness wire between the injector driver relay and
the injector driver, and repair if necessary.NG
Repair
NG
Repair
NG
Repair NG
Repair
Measure at the injector driver relay connector B-28X.
DDisconnect the connector, and measure at the harness
side.
(1) The voltage between terminal 3 and earth
OK:
System voltage
(2) The voltage between terminal 4 and earth (Ignition switch:
ON)
OK:
System voltage


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-191
Inspection procedure 27
Ignition switch-ST and inhibitor switch system
Probable cause
The ignition switch-ST inputs a HIGH signal to the engine-A/T-ECU while the
engine iscranking. The engine-A/T-ECU controls fuel injection, etc. during
starting based on this input.
The inhibitor switch inputs the position of the selector lever to the
engine-A/T-ECU. The engine-A/T-ECU uses this signal to carry outidlespeed
control.DMalfunction of the ignition switch
DMalfunction of the inhibitor switch
DOpen circuit or short-circuited harness wire
between the ignition switch and the inhibitor
switch, or improper connector contact.
DMalfunction of the engine-A/T-ECU
OK
Check the following connector:
D-120
OK
Ignition switch check
(Refer to GROUP 54 - Ignition Switch.)
OK
Check the trouble symptoms.
OK
Check the trouble symptoms.
MUT-
IIData list
Confirm the data list concerning the A/T system.
61 Inhibitor switch
(Refer to GROUP 23 - Troubleshooting.)NGCheck the inhibitor switch system.
(Refer to GROUP 23 - Troubleshooting.)
OK
Measure at engine-A/T-ECU connector D-120.
DDisconnect the connector, and measure at the harness
side.
DThe voltage between terminal 58 and earth
(Selector lever position: P or N)
(Ignition switch: START)
OK:
System voltageNGCheck the following connector:
C-05
NG
Repair
NG
Check the harness between the inhibitor switch and the
ignition switch.
OK
Check the trouble symptoms.
NG
Repair
OK
Check the inhibitor switch.
DThe continuity between terminals 9 and 10 (Refer to
GROUP 23 - On-vehicle Service.)NGReplace
NG
Replace the engine-A/T-ECU.
NG
Repair
NG
Check the harness wire between the inhibitor switch and the
engine-A/T-ECU, and repair if necessary.
OK
Measure at inhibitor switch connector C-05.
DDisconnect the connector, and measure at the harness
side.
DThe voltage between terminal 10 and earth (Ignition switch:
ON)
OK:
System voltageNGCheck the following connector:
E-114
NG
Repair


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-192
Inspection procedure 28
Accelerator pedal position switch system
Probable cause
The accelerator pedal positionswitch detects that the acceleratorpedal isfully
closed, and sends a signal to the engine-A/T-ECU. The engine-A/T-ECU uses
this signal to carry outidlespeed control.DMaladjustment of the accelerator pedal position
switch and the acceleratorpedal positionsensor.
DOpen circuit or short-circuited harness wire in the
accelerator pedal positionswitch system, or poor
connector contact
DMalfunction of the engine-A/T-ECU
OK
Check the trouble symptoms.NGReplace the engine-A/T-ECU.
OK
Check the acceleratorpedal position
switch. (Refer to P.13A-230.)NGReplace the accelerator pedal
position sensor.
OK
Measure at accelerator pedal position
sensor connector D-135.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 4
and earth
(Ignition switch: ON)
OK:
4 V or more
DThe continuity between terminal 5
and earth
OK:
ContinuityNGCheck the following connector:
D-121NG
Repair
OK
Check the trouble symptoms.
NG
NG
Check the harness wire between the
engine-A/T-ECU and the accelerator
pedal positionsensor.Repair
OK
Check the following connector:
D-135NG
Repair


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-193
Inspection procedure 29
Fuel pump (low pressure) system
Probable cause
The engine-A/T-ECU turns on the fuelpumprelay while theengine iscranking
or running, and supplies power source to the fuelpump(low pressure).DMalfunction of the fuel pumprelay
DMalfunction of the fuel pump(low pressure)
DImproper connector contact,opencircuit or
short-circuited harness wire
DMalfunction of the engine-A/T-ECU
Check the ignition switch (Refer to
GROUP54 - Ignition Switch.)
NG
Repair
OK
OK
NG
OK
Check the trouble symptoms.NGReplace the fuel pump(low
pressure).
NG
Replace the engine-A/T-ECU.OKRepair
OK
Normal
NG
Repair
NG
Check the harness wire between the
fuel pumprelay and the fuelpump
(low pressure). NG
(1) NG
NG
NG
Check the harness wire between the
fuel pump(low pressure) and earth,
and repair if necessary.
(2) NG
NG
NG
NG
Repair
OK
OK
Check the following connector:
G-12NG
Repair
Check the trouble symptoms.
Check the following connector
:
F-11
OK
Check the trouble symptoms.
Check the following connectors:
B-27X, D-124, E-17, F-11Measure at fuel pump(low pressure)
connector G-12.
DDisconnect the connector, and
measure at the harness side.
(1) The voltage between terminal 5
and earth
(Ignition switch: ON)
OK:
System voltage
(2) The continuity between terminal 4
and earth
OK:
Continuity
Check the trouble symptoms.
OK
Measure at the engine-A/T-ECU
connector D-119.
DDisconnect the connector, and
measure at the harness side.
DShort circuit between terminal 21
and earth
(Ignition switch: ON)
OK:
The fuel pump operates.
(Its operation sound can be
heard.)OKCheck the following connector
:
D-119
OK
Measure at the engine-A/T-ECU
connector D-119.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 21
and earth
(Ignition switch: ON)
OK:
System voltageNGCheck the harness wire between the
fuel pumprelay and the
engine-A/T-ECU, and repair if
necessary.
Check the harness wire between the
fuel pumprelay and the ignition
switch.
OK
Check the trouble symptoms.
Check the following connectors:
D-208, D-213, E-10Measure at the fuel pumprelay
connector B-27X.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 3,
4 and earth
(Ignition switch: ON)
OK:
System voltage
OK
Check the fuelpumprelay (Refer to
P.13A-227.)NG
Replace
MUT-
IIActuator Test
07 Fuel pump
(Refer to P.13A-203.)
Repair


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-194
Inspection procedure 30
Power steering fluid pressure switch system
Probable cause
The presence or absence of power steeringload is input to the engine-A/T-ECU.
Based on this signal, the engine-A/T-ECU controls the throttle control servo so
that idlespeed increases when the power steering is in operation.DMalfunction of the power steering fluid pressure
switch.
DImproper connector contact,opencircuit or
short-circuited harness wire
DMalfunction of the engine-A/T-ECU
OK
Measure at power steering fluid
pressure switch connector B-51.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 1
and earth
(Ignition switch: ON)
OK:
System voltageNGCheck the following connector:
D-120NG
Repair
OK
Check the trouble symptoms.
NG
Check the harness wire between the
engine-A/T-ECU and the power
steering fluid pressure switch, and
repair if necessary.OK
Check the following connector:
B-51NG
Repair
OK
Check the trouble symptoms.NGReplace the engine-A/T-ECU.
Check the power steering fluid
pressure switch (Refer to GROUP
37A - On-vehicle Service.)NG
Replace
Inspection procedure 31
A/C switch and A/C relay system
Probable cause
When an A/C ON signal is input to the engine-A/T-ECU, the engine-A/T-ECU
controls the throttle control servo so thatidlespeed increases, and also operates
the A/C compressor magnetic clutch.DMalfunction of the A/C control system
DMalfunction of the A/C switch
DImproper connector contact,opencircuit or
short-circuited harness wire
DMalfunction of the engine-A/T-ECU
Service the A/C compressor relay.
(Refer to GROUP 55 - On-vehicle
Service.)NG
Replace
OK
Measure at engine-A/T-ECU
connectors D-119, D-121.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 20,
83 and earth
(Ignition switch: ON)
OK:
0-3V
(A/C switch: OFF)
System voltage
(A/C switch: ON)
DConnect terminal 20 to earth.
(Ignition switch: ON, A/C switch:
ON)
OK:
A/C compressor clutch
turns on.OKCheck the following connectors:
D-119, D-121NG
Repair
OK
Check the trouble symptoms.
NG
Replace the engine-A/T-ECU.
NG
Check the A/C system (Refer to
GROUP 55 - Troubleshooting.)


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-195
Inspection procedure 32
Stop lamp switch system
Probable cause
The engine-A/T-ECU determines whether the brakepedal is depressed or not.
The engine-A/T-ECU selects a fuel injectionmode by determining thebrake
operation according to this information.DMalfunction of the stoplampswitch
DImproper connector contact,opencircuit or
short-circuited harness wire
DMalfunction of the engine-A/T-ECU
NG
Check the following connectors:
D-26 <LHD>, D-27, D-124 <RHD>NG
Repair
OK
Check the trouble symptoms.
OK
Check the following connector:
D-122NG
Repair
Stoplampswitch check (Refer to
GROUP 35 - Brake Pedal.)NG
Replace
OK
Measure at stoplampswitch
connector D-136.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 2
and earth
OK
System voltageOKMeasure at the engine-A/T-ECU
connector D-122.
DDisconnect the connector, and
measure at the harness side.
DThe voltage between terminal 123
and earth
(Ignition switch: ON)
OK
0 - 3 V (when the brake
pedal is not depressed)
System voltage (when the
brakepedal is depressed)NG
NG
Repair OK
Check the trouble symptoms.
NG
Check the harness wire between the
engine-A/T-ECU and the stoplamp
switch, and repair if necessary.
NG
Check the harness wire between the
battery and the stoplampswitch,
and repair if necessary.
OK
Check the trouble symptoms.NGReplace the engine-A/T-ECU.
Check the following connectors:
D-26 <LHD>, D-33, D-128, D-136,
D-124 <RHD>, E-13
Inspection procedure 33
Small lamp switch system
Probable cause
The engine-A/T-ECU determines whether the smalllampswitch is on or off.
According to that information, the engine-A/T-ECU controls alternator output
current when the vehicle is started.DImproper connector contact,opencircuit or
short-circuited harness wire in thetaillamprelay
circuit.
DMalfunction of the engine-A/T-ECU
OK
Check the following connector:
D-121NGReplace
Measure at engine-A/T-ECU connector D-121.
DDisconnect the connector, and measure at the harness
side.
DThe voltage between terminal 86 and earth (Lighting
switch: ON)
OK:
System voltageNGCheck thetaillampcircuit. (Refer to ELECTRICAL WIRING.)
OK
Check the trouble symptoms.
NG
Replace the engine-A/T-ECU.


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

GDI -Troubleshooting <A/T>13A-196
Inspection procedure 34
Injector driver
Probable cause
The engine-A/T-ECU drives the injector by the drive signal.DMalfunction of the injector driver
DImproper connector contact,opencircuit or
short-circuited harness wire
DMalfunction of the engine-A/T-ECU
OK
NG
Replace the engine-A/T-ECU.
OK
Check the trouble symptoms.Transient malfunction
(Refer to GROUP 00 - Points to Note for Intermittent
Malfunctions.) OK
Use a analyzer to measure the signal waveform at the engine-
A/T-ECU connectors D-119 and D-120.
DEngine: idling
DSelector lever position: P
DVoltage between 96 and earth, and between 1 and earth
OK:
A normal waveform should be displayed as described
on P.13A-214 (INSPECTIONPROCEDURE USING
AN ANALYZER).NGReplace the injector driver.
NGCheck the following connectors:
B-121, D-119Repair
NG
Repair
OK
Check the harness wire between the injector driver and engine-
A/T-ECU.
Inspection procedure 35
EGR valve (stepper motor) system
Probable cause
The engine-A/T-ECU controls the EGR valve (stepper motor) in order to control
the amount ofexhaust gas mixed in the intake air.DMalfunction of the EGR valve
DOpen circuit or short-circuited harness wire in the
EGR valve circuit
DMalfunction of the engine-A/T-ECU
OK
Check the trouble symptoms.NGCheck the harness wire between the
engine controlrelay and the EGR valve,
and repair if necessary.
OK
Check the trouble symptoms.NGCheck the harness wire between the
engine-A/T-ECU and EGR valve, and
repair if necessary.
OK
Check the trouble symptoms.NGReplace the engine-A/T-ECU.
OK
Check the following connector:
D-120NG
Repair
OK
Measure at the engine-A/T-ECU con-
nector D-120.
DDisconnect the connector, and
measure at the harness side.
DVoltage between 51, 53, 60, 62
and earth (Ignition switch: ON)
OK:
System voltageNGCheck the following connector:
B-60NG
Repair
OK
Measure at the EGR valve connector
B-60.
DDisconnect the connector, and
measure at the harness side.
DVoltage between 2, 5 and earth
(Ignition switch: ON)
OK:
System voltageNGCheck the following connector:
B-25XNG
Repair
Check the EGR valve. (Refer to GROUP
17 - Emission Control System.)NG
Replace


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk