MITSUBISHI MONTERO 2000 Service Repair Manual

DIESEL FUEL <4M4> -Troubleshooting13C-10
Code No. 13 Barometric pressure sensor systemProbable cause
Range of Check
DIgnition switch: ON, except for duringenginecranking
Set Conditions
DThe sensor output voltage is for 3 seconds is 4.5V or higher (the barometric
pressure is approximately 120 kPa or over).
or
DThe sensor output voltage is for 3 seconds is 1.5V or lower (the barometric
pressure is approximately 33 kPa or under).Engine-ECU inoperative
Replace the engine-ECU.NGCheck the trouble symptoms.
Code No. 14 Fuel temperature sensor systemProbable cause
Range of Check
DIgnition switch: ON, except for duringenginecranking
Set Conditions
DThe sensor output voltage for 3 seconds is 0.2V or higher (the fuel
temperature is approximately 120°C or higher).
or
DThe sensor output voltage for 3 seconds is 4.6V or lower (the fuel
temperature is approximately 50°C or lower).DFuel temperature sensor inoperative
DFuel temperature sensoropencircuit, short circuit,
or connector contact inoperative
DEngine-ECU inoperative
OK
Measure at B-38 fuel temperature sensor
connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 11 and the earth
(Ignition switch: ON)
OK:
4.5 - 5.5 V
DContinuity between 7 and the earth
OK:
ContinuityNGCheck the following connectors:
D-112, D-113NG
Repair
OK
OK
Check the harness between the
engine-ECU and the fuel temperature
sensor connector.Repair
NG
Check the trouble symptoms.
Replace the engine-ECU.NG
Replace the engine-ECU.OKNG
Replace the injection pump.
OK
Repair
Check the following connector:
B-38
NG
NGCheck the trouble symptoms.
Fuel temperature sensor check (Refer to
P.13C-47.)


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DIESEL FUEL <4M4> -Troubleshooting13C-11
Code No. 15 Engine coolant temperature sensor systemProbable cause
Range of Check
DIgnition switch: ON, except for duringenginecranking
Set Conditions
DThe sensor output voltage for 3 seconds is 4.9V or higher (the coolant
temperature is approximately - 45_C or lower).
or
DThe sensor output voltage for 3 seconds is 0.2V or lower (the coolant
temperature is approximately 140_C or higher).DEngine coolant temperature sensor inoperative
DEngine coolant temperature sensoropencircuit,
short circuit, or connector contact inoperative
DEngine-ECU inoperative
OK
NGNG
Repair
OK
OKRepair
NGEngine coolant temperature sensor check
(Refer to P.13C-38.)
Replace the engine-ECU.NG
Replace the engine-ECU.OK NG
OK
Repair
Check the following connector:
B-36-3
NGCheck the trouble symptoms.NG
Measure at B-36-3 engine coolantsensor
connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 1 and the earth
(Ignition switch: ON)
OK:
4.5 - 5.5 V
DContinuity between 2 and the earth
OK:
ContinuityCheck the following connectors:
B-36, D-112, D-113
Check the harness between the
engine-ECU and the engine coolant
temperature sensor connector.
Check the trouble symptoms. Replace
Code No. 16 Boost air temperature sensor (intake air
sensor) systemProbable cause
Range of Check
DIgnition switch:ON, except for duringenginecranking
Set Conditions
DThe sensor output voltage for 3 seconds is 4.6V or higher (the coolant
temperature is approximately 45_C or lower).
or
DThe sensor output voltage for 3 seconds is 0.3V or lower (the coolant
temperature is approximately 110_C or higher).DBoost air temperature sensor inoperative
DBoost air temperature sensoropencircuit, short
circuit, or connector contact inoperative
DEngine-ECU inoperative
OK
Measure at B-49 boost air temperature
connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 1 and the earth
(Ignition switch: ON)
OK:
4.0 - 5.3 V
DContinuity between 2 and the earth
OK:
ContinuityNGCheck the following connectors:
D-112, D-113NG
Repair
OK
OKRepair
NGBoost air temperature sensor check
(Refer to P.13C-44.)
Check the trouble symptoms.
Replace the engine-ECU.NG
Replace the engine-ECU.OK NG
OK
Repair
Check the following connector:
B-49Replace
NGCheck the trouble symptoms.NG
Check the harness between the
engine-ECU and the boost air temperature
sensor connector.


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DIESEL FUEL <4M4> -Troubleshooting13C-12
Code No. 17 Vehicle speed sensor systemProbable cause
Range of Check
DIgnition switch: ON
DEngine speed: 2800 r/min or higher
DDriving with heavyload
Set Conditions
DSlower than vehicle speed of 3 km/hDVehicle speed sensor inoperative
DVehicle speed sensoropencircuit, short circuit, or
connector contact inoperative
DEngine-ECU inoperative
NG
YES
OK
Check the following connector:
D-113NG
Repair
OK
Check and repair the harness between the
engine-ECU and the vehicle speed sensor
connector
NOIs the speed meter working properly?
Check the trouble symptoms.
Replace the engine-ECU.
NG
OK
Repair
Check the following connectors:
C-09, D-113, E-113
NGCheck the trouble symptoms.NG
Vehicle speed sensor circuit check
Measure at D-113 engine-ECU connector
DConnect the connector.
DVoltage between 86 and the earth
(Ignition switch: ON)
OK:
When the vehicle is pushed to
move, the cycle change of 0.5 V is
repeated.


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DIESEL FUEL <4M4> -Troubleshooting13C-13
Code No. 18 Engine speed sensor (backup) systemProbable cause
Range of Check
DExcept for duringengine running andcranking
Set Conditions
DThe difference in the enginespeed sensor output for 4 seconds: 325 r/min or
moreDEngine speed sensor inoperative
DEngine speed sensoropencircuit, short circuit, or
connector contact inoperative
DEngine-ECU inoperative
Check the trouble symptoms.
OK
Check and repair the harness
between the enginespeed sensor
and the control relay connector.OK
OK
NG
Repair
(1) NGMeasure at B-36-2 enginespeed
sensor connector
DConnect the connector.
(Test harness: MB998348 used)
DVoltage between 2 and the earth
(Engine: cranking)
OK:
0.4 - 4.0 V
DVoltage between 2 and the earth
(Engine: Idling)
OK:
1.5 - 2.5 V
NG
Replace the enginespeed sensor.
Replace the engine-ECU.
Check the following connector:
B-36
NG
NG
Check the trouble symptoms.
OK
Repair NG
OK
Repair NG NG
OKRepair NG
NG
OKRepair NG
Check the following connector:
B-36-2
Check the trouble symptoms.
Measure at B-36-2 enginespeed
sensor connector
DDisconnect the connector and
measure at the harness side.
(1) Voltage between 3 and the earth
(Ignition switch: ON)
OK:
System voltage
(2) Voltage between 2 and the earth
(Ignition switch: ON)
OK:
4.8 - 5.2V
(3) Continuity between 1 and the
earth
OK:
Continuity(2) NG
(3) NG
Check the harness between the
engine-ECU and the enginespeed
sensor connector.
Replace the engine-ECU.
Check and repair the harness
between the enginespeed sensor
and the earth.
Check the following connector:
B-36
Check the trouble symptoms.
Check the following connectors:
B-36, D-112


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DIESEL FUEL <4M4> -Troubleshooting13C-14
Code No. 21 Engine speed sensor systemProbable cause
Range of Check
DDuring enginecranking
Or
DExcept for duringengine running andcranking
Set Conditions
DNo change in the sensor output voltage for 3 seconds (no pulse signal has
been input).
Or
DNo change in the enginespeed sensor output for 0.06 seconds (for backup),
or in the sensor output for 0.3 secondsDEngine speed sensor inoperative
DEngine speed sensoropencircuit, short circuit, or
connector contact inoperative
DEngine-ECU inoperative
OK
Check and repair the harness
between the enginespeed sensor
and the control relay connector.OK
OK
NG
Repair
(1) NGMeasure at B-36-1 enginespeed
sensor connector
DConnect the connector.
(Test harness: MB998348 used)
DVoltage between 2 and the earth
(Engine: cranking)
OK:
0.4 - 4.0 V
DVoltage between 2 and the earth
(Engine: idling)
OK:
1.5 - 2.5 V
NG
Replace the enginespeed sensor.
Replace the engine-ECU.
Check the following connector:
B-36
NG
NG
Check the trouble symptoms.
OK
Repair
Check the following connectors:
B-36, D-112
NG
OK
Repair NG
Check the harness between the
engine-ECU and the enginespeed
sensor connector.NG
Check the trouble symptoms.
Replace the engine-ECU.
Check and repair the harness
between the enginespeed sensor
and the earth.OK
Repair
Check the following connector:
B-36
NG
NG
Check the trouble symptoms. OK
Repair NG
Check the following connector:
B-36-1
Check the trouble symptoms.
Measure at B-36-1 enginespeed
sensor connector
DDisconnect the connector and
measure at the harness side.
(1) Voltage between 3 and the earth
(Ignition switch: ON)
OK:
System voltage
(2) Voltage between 2 and the earth
(Ignition switch: ON)
OK:
4.8 - 5.2V
(3) Continuity between 1 and the
earth
OK:
Continuity(2) NG
(3) NG


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DIESEL FUEL <4M4> -Troubleshooting13C-15
Code No. 23 Idle switch (accelerator pedal position
sensor built-in) systemProbable cause
Range of Check
Ignition switch: ON, acceleratorpedal positionsensor (main, sub) operative,
except for duringenginecranking
Set Conditions
DFor 1 minute idleswitch (built-in): ON, acceleratorpedal positionsensor
(main, sub) output voltage 1.875V or higher or 10 minutes
DIdle switch (built-in): OFF, acceleratorpedal positionsensor (main, sub)
opening degreesless than 1%DAcceleratorpedal positionsensor inoperative
DAcceleratorpedal positionsensoropencircuit,
short circuit, or connector contact inoperative
DIdle switch “ON” inoperative
DIdle switch signallineshort circuit
DEngine-ECU inoperative
OK
Measure at D-135 acceleratorpedal position
sensor connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 4 and the earth
(Ignition switch: ON)
OK:
4.5 - 5.5 V
DContinuity between 5 and the earth
OK:
ContinuityNGCheck the following connectors:
D-111, D-112NG
Repair
OK
OKRepair
NGAcceleratorpedal positionsensor check
(Refer to P.13C-43.)
Check the trouble symptoms.
Replace the engine-ECU.NG
Replace the engine-ECU.OKNG
OK
Check the following connector:
D-135Replace
NG
Check the trouble symptoms.
Check the harness between the
engine-ECU and the accelerator pedal
position sensor connector.
NG
Repair


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P
ro bab le cau se O
K M
easu re at B-3 9 tim er pis to n posit io n se nso r
c o nnecto r
D Dis co nnect th e co nnecto r and measu re at
t h e harn ess wit h an analo gue vo lt m ete r.
D Volt a ge betw een 3and th e earth
( Ig nit io n sw it c h : O N)
O K:
2.5 V fix e d vo lt a ge
D Volt a ge betw een 1and th e earth *2
( Ig nit io n sw it c h : O N)
O K:
Appro x. 1.4 -2.3 V
D Volt a ge betw een 2and th e earth *2
O K:
Appro x. 1.4 -2.3 V N
G O
K R
ep air T
im er pis to n posit io n se nso r ch eck (R efe r to
P .1 3C -4 7.) R
epla ce th e engin e-E C U. N
G O
K
N
G
O K N
G C
heck th e tr o uble sym pto m s. R
epla ce in je ctio n pum p asse m bly . N
G R
epla ce th e engin e-E C U.
R
ep air N
G C
heck th e tr o uble sym pto m s. R
epla ce in je ctio n pum p asse m bly (tim er
p is to n fu lly clo se d/o pened posit io n
i n opera tiv e , etc .) C
heck th e tr o uble sym pto m s.
N G O
K C
heck th e harn ess betw een th e
e ngin e-E C U and th e tim er pis to n se nso r
c o nnecto r. R
epla ce th e engin e-E C U.
w
ww.W ork sh opM an uals .c o .u k
P urc h ased f r o m w ww.W ork sh opM an uals .c o .u k

P
ro bab le cau se 2
.5 V
1 2.5 V
66 mic ro se c
N O TE :
* 1
: T his vo lt a ge is deriv e d fr o m th e in putp uls e sig nalc o nve rte d in th e engin e-E C U and ca nnotb e m easu re d.
* 2
: This vo lt a ge is sh ow n as a sq uare wave wit h a cycle of 16.7 mic ro se c (H ig h: 2.5 V , Low : 1.2 5 V .) M
easu re at B-3 8 in je ctio n pum p asse m bly
c o nnecto r
D Dis co nnect th e co nnecto r and measu re at
t h e harn ess wit h an analo gue vo lt m ete r.
D Volt a ge betw een 8and th e earth
( Ig nit io n sw it c h : O N)
O K:
2.5 V fix e d vo lt a ge
D Volt a ge betw een 4and th e earth *2
( Ig nit io n sw it c h : O N)
O K:
Appro x. 1.4 -2.3 V
D Volt a ge betw een 12 and th e earth *2
O K:
Appro x. 1.4 -2.3 V N
G O
K R
ep air C
ontr o l sle eve posit io n se nso r ch eck (R efe r
t o P.1 3C -4 7.) R
epla ce th e engin e-E C U. N
G O
K
N
G
O K N
G C
heck th e tr o uble sym pto m s. R
epla ce in je ctio n pum p asse m bly . N
G R
epla ce th e engin e-E C U.
R
ep air N
G C
heck th e tr o uble sym pto m s. R
epla ce in je ctio n pum p asse m bly . C
heck th e tr o uble sym pto m s.
N G O
K C
heck th e harn ess betw een th e
e ngin e-E C U and th e in je ctio n pum p
a sse m bly co nnecto r. R
epla ce th e engin e-E C U.
w
ww.W ork sh opM an uals .c o .u k
P urc h ased f r o m w ww.W ork sh opM an uals .c o .u k

DIESEL FUEL <4M4> -Troubleshooting13C-18
Code No. 27 Accelerator pedal position sensor (sub)
systemProbable cause
Range of Check
DIgnition switch: ON, acceleratorpedal positionsensor (main) operative, except
for during enginecranking
Set Conditions
DOutput voltage of accelerator pedal positionsensor (main) for 1 second is
0.2V or higher and lower than 2.5V. Output voltage of acceleratorpedal
position sensor (sub) for 1 second is 4.5V or higher, or lower than 0.2V.
Range of Check
DIgnition switch: ON, except for duringenginecranking
Set Conditions
DOutput voltage of accelerator pedal positionsensor (main, sub) for 1 second
is 0.2 V or higher or lower than 4.5V. The difference in the output sensor
voltage between the main and the subsensor is 1V or higher, or theidle
switch ON, and sensormain output voltage is 1.875V or higher.DAcceleratorpedal positionsensor inoperative
DAcceleratorpedal positionsensoropencircuit,
short circuit, or connector contact inoperative
DEngine-ECU inoperative
OK
Measure at D-135 acceleratorpedal position
sensor connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 8 and the earth
(Ignition switch: ON)
OK:
4.5 - 5.5 V
DContinuity between 7 and the earth
OK:
ContinuityNGNG
Repair
OK
OKRepair
NGAcceleratorpedal positionsensor check
(Refer to P.13C-43.)
NG
Replace the engine-ECU.OKNG
OK
Replace
NG
Check the trouble symptoms.
NG
RepairCheck the following connector:
D-135
Check the harness between the
engine-ECU and the accelerator pedal
position sensor connector.
Check the trouble symptoms.
Replace the engine-ECU.
Check the following connector:
D-112


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DIESEL FUEL <4M4> -Troubleshooting13C-19
Code No. 41 Main throttle solenoid valve systemProbable cause
Range of Check
DEngine speed is 1600 r/min or higher and the accelerationopening degree is
60% or more.
Set Conditions
DBoost pressure is lower than barometric pressure + 30 kPa for two seconds.
Range of Check
DWith the idlingspeed controlled, theengine warmed up, and no failure found
Set Conditions
DBoost pressure is higher than barometric pressure - 2.7 kPa for 3 seconds.DMain throttle solenoidvalve inoperative
DMain throttle solenoidvalveopencircuit, short
circuit, or connector contact inoperative
DEngine-ECU inoperative
OK
Check the following connector:
B-45NG
Repair
OK
OK
Check and repair the harness between the
control relay and the solenoid valve
connector.
Main throttle solenoidvalve check (Refer to
P.13C-48.)
Check the trouble symptoms.
Replace the engine-ECU.
NG
OK
RepairCheck the following connector:
D-110
Check the trouble symptoms.NGReplace
NG NG
Check the following connectors:
B-45, B-45-2NG
Repair
OK
Check and repair the harness between the
control relay and the solenoid valve
connector.
Check the trouble symptoms.
NG
NGMeasure at D-110 engine-ECU connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 14 and the earth
(Ignition switch: ON)
OK:
System voltageOK
Measure at B-45-2 main throttle solenoid
valve connector
DDisconnect the connector and measure at
the harness side.
DVoltage between 1 and the earth
(Ignition switch: ON)
OK:
System voltage


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