MITSUBISHI MONTERO 2000 Service Repair Manual

T
R O UBLE SH O OTIN G
S TA NDARD FLO W OF DIA G NO SIS TR O UBLE SH O OTIN G
R efe r to GRO UP 00 -How to Use Tro uble sh ootin g/In sp ectio n Serv ic e Poin ts .
N O TE
C heck th at th e va cu um hose is co nnecte d co rre ctly and is not dam aged, and th en ca rry out th e dia gnosis .
D IA G NO SIS FU NCTIO N
M ETH O D OF REA DIN G TH E DIA G NO SIS CO DES
U sin g th e MUT-I
I
1 . Connect th e MUT-I
I
to th e dia gnosis co nnecto r (1 6-p in )
u nder th e in str u m ent under co ve r.
2 . Wit h th e ig nit io n sw it c h in th e ON posit io n,ta ke are adin g
o f th e dia gnosis co des.
C au tio n
T u rn off th e ig nit io n sw it c h befo re co nnectin g or
d is co nnectin g th e MUT-I
I
.
U sin g aAuto -c ru is e Contr o l In dic ato r Lam p
1 . Turn th e ig nit io n sw it c h ON wit h th e SET sw it c h on.T hen,
t u rn th e RESU M E sw it c h ON wit h in 1se co nd.
2 . Read a dia gnosis co de by obse rv in g th e fla sh dis p la y
p atte rn of th e auto -c ru is e co ntr o l in dic a to r la m p in th e
c o m bin atio n mete r.
I n dic atio n of dia g nosis co de by au to -c ru is e co ntr o l in dic ato r la m p
W hen th e dia gnosis co de No.2 3 is outp ut W
hen no dia gnosis co de is outp ut 1
2V 0
V 1
.5 s 0
.5 s
P ause
t im e:3 s 0
.5 s C
ontin uous ON and OFF
s ig nals atin te rv a ls of0 .5 s
1
2 V
0 V 0
.5 s D
ia gnosis
c o nnecto r A
uto -c ru is e
c o ntr o lsw it c h R
ESU M E
s w it c h : O N S
ET
s w it c h : O N
w
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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-10
METHOD OF ERASING THE DIAGNOSIS
CODES
Refer to GROUP 00 - How to Use Troubleshooting/Inspection
Service Points.
INSPECTION CHART FOR DIAGNOSIS CODES <6G7>
Code No.Diagnosis itemReference page
15Auto-cruise control switch system17-10
21Cancel latch signal system17-11
22Stop lamp switch system17-11
23Engine-ECU orengine-A/T-ECU system17-12
INSPECTION PROCEDURE FOR DIAGNOSIS CODES <6G7>
Code No. 15 Auto-cruise control switch systemProbable cause
This diagnosis code is output if the RESUME and SET switches of the auto-cruise
control switch remain on.DMalfunction of the auto-cruise control switch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
Repair
Check the auto-cruise control switch. (Refer to P.17-29.)NG
Replace
OK
Check the following connectors:
D-205-3, D-205-2, D-205, E-10, D-11NG
Repair
NGCheck the harness between the auto-cruise control switch and
throttle valve controller.
NG
OK
Replace the throttle valve controller.
OK
Check trouble symptom.
Check trouble symptom.
NG


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-11
Code No. 21 Cancel latch signal systemProbable cause
The throttle valve controller and engine-ECU or engine-A/T-ECU send
a cancelholding information to the engine-ECU or engine-A/T-ECU
via a cancel latch signal line and the serial communication line.
This diagnosis code is output if there is a failure in the cancel latch signal line, or
a disaccord in the communication data.DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
Repair NG
RepairCheck the following connectors:
D-118, D-122, D-11NG
OK
Replace the throttle valve controller.
NG
NG
Check the harness between the throttle valve controller and engine-
ECU or engine-A/T-ECU .
Replace the engine-ECU or engine-A/T-ECU
Check trouble symptom.
OK
Check trouble symptom.
Check trouble symptom.NG
Code No. 22 Stop lamp switch systemProbable cause
This diagnosis code is output when the throttle valve controller detects a failure in
the stoplampswitch output.DMalfunction of the stoplampswitch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
(2)NG
NG
Check the harness between the throttle valve connector and stop
lampswitch, and body earth, and repair if necessary.
NG
Repair
OK
Check trouble symptom.
Measure at the throttle valve controller connector D-11.
DDisconnect the connector and measure at the harness side.
(1) Voltage between terminal 25 and body earth
OK:0V (When brakepedal is not depressed.)
System voltage (When brakepedal is depressed.)
(2) Continuity between terminal 26 and body earth
OK:Continuity (When brakepedal is not depressed.)
No continuity (When brakepedal is depressed.)NO
Do the stop lamps illuminate normally?
OK
To the next page.
Check the following connectors:
D-136, D-26, D-33, E-13, D-128, D-11
D-136, D-124, E-13, D-128, D-11
OK
Check trouble symptom.
NG
Check the harness between the stoplampswitch and throttle valve
controller, and repair if necessary.NG
Repair
Check the stoplampcircuit.
YES
(1)NG
Check the following connectors:
D-136, D-26, E-10, D-11
D-136, D-124, E-10, D-11


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-12
NG
Check the harness between the joint connector (4) and engine-ECU
or engine-A/T-ECU , and repair if necessary.
NG
Repair
OK
Check trouble symptom.
From the previous page.
OK
Check the following connectors:
D-128, D-63
D-128, D-122
OK
Check trouble symptom.
NG
Replace the throttle valve controller.NG
Measure at the engine-ECU connector D-117 or engine-A/T-
ECU connector D-122.
DDisconnect the connector and measure at the harness side.
DVoltage between terminal 63 and body earth or
voltage between terminal 123 and body earth
OK:0V (When brakepedal is not depressed.)
System voltage (When brakepedal is depressed.)
Code No. 23 Engine-ECU or engine-A/T-ECU
systemProbable cause
This diagnosis code is output if the engine-ECU or engine-A/T-ECU
system is defective as follows:
DCommunication error between the throttle valve controller and the engine-ECU

DCommunication error between the throttle valve controller and the engine-A/T-ECU

DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
DMalfunction of the throttle position sensor
DMalfunction of the accelerator pedal positionsensor
DMalfunction of the throttle control servo
DMalfunction of the vehicle speed sensorDMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
MUT-
IISelf-Diag code
Confirm diagnosis code regarding the GDI system.Diagnosis
code outputCarry out the troubleshooting regarding the GDI system.
(Refer to GROUP 13A.)
No diagnosis code output
Check trouble symptom.


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-13
INSPECTION CHART FOR DIAGNOSIS CODES <4M4>
Code No.Diagnosis itemReference page
15Auto-cruise control switch system17-13
22Stop lamp switch system17-14
23Engine-ECU system17-14
INSPECTION PROCEDURE FOR DIAGNOSIS CODES <4M4>
Code No. 15 Auto-cruise control switch systemProbable cause
This diagnosis code is output if the RESUME and SET switches of the auto-cruise
control switch remain on.DMalfunction of the auto-cruise control switch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the engine-ECU
Repair
Check the auto-cruise control switch. (Refer to P.17-29.)NG
Replace
OK
Check the following connectors:
D-205-3, D-205-2, D-205, E-10, D-111NG
Repair
NGCheck the harness between the auto-cruise control switch and
engine-ECU.
NG
OK
Replace the engine-ECU.
OK
Check trouble symptom.
Check trouble symptom.
NG


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-14
Code No. 22 Stop lamp switch systemProbable cause
This diagnosis code is output when the engine-ECU detects a failure in the stop
lampswitch output.DMalfunction of the stoplampswitch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the engine-ECU
(2)NG
NG
Check the harness between the engine-ECU and stoplampswitch,
and body earth, and repair if necessary.
NG
Repair
OK
Check trouble symptom.
Measure at the engine-ECU connector D-111.
DDisconnect the connector and measure at the harness side.
(1) Voltage between terminal 39 and body earth
OK:0V (When brakepedal is not depressed.)
System voltage (When brakepedal is depressed.)
(2) Continuity between terminal 40 and body earth
OK:Continuity (When brakepedal is not depressed.)
No continuity (When brakepedal is depressed.)NO
Do the stop lamps illuminate normally?
OK
Check trouble symptom.
Check the following connectors:
D-136, D-26, D-33, E-13, D-128, D-111
D-136, D-124, E-13, D-128, D-111
OK
Check trouble symptom.
NG
Check the harness between the stoplampswitch and engine-ECU,
and repair if necessary.NG
Repair
Check the stoplampcircuit.
YES
(1)NG
Check the following connectors:
D-136, D-26, E-10, D-111
D-136, D-124, E-10, D-111 NG
Replace the engine-ECU.
Code No. 23 Engine-ECU systemProbable cause
This diagnosis code is output if the engine-ECU system is defective as follows:
DMalfunction of the engine-ECU
DMalfunction of the accelerator pedal positionsensor
DMalfunction of the GE actuator (electronic governor)
DMalfunction of the vehicle speed sensorDMalfunction of the engine-ECU
MUT-
IISelf-Diag code
Confirm diagnosis code regarding the diesel fuel system.Diagnosis
code outputCarry out the troubleshooting regarding the diesel fuel system.
(Refer to GROUP 13C.)
No diagnosis code output
Check trouble symptom.


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ENGINE AND EMISSION CONTROL -Auto-cruise Control SystemENGINE AND EMISSION CONTROL -Auto-cruise Control System17-15
INSPECTION CHART FOR TROUBLE SYMPTOMS <6G7>
Trouble symptomInspection
procedure No.Reference page
Communication with MUT-IIis not possible.117-15
Auto-cruise control isEven if brake pedal is depressed217-16
not cancelled.
Even if clutch pedal is depressed317-16
Even if select lever is set to N range417-17
Even if CANCEL switch is set to ON517-17
Auto-cruise control cannot be set.617-17
Hunting (repeated acceleration and deceleration) occurs at the set vehicle speed.717-18
When the MAIN switch of the auto-cruise control switch is turned ON, the
auto-cruise control indicator lamp does not illuminate. (However, the auto-cruise
control system is normal.)817-18
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS <6G7>
Inspection Procedure 1
Communication with MUT-II
is not possible.
Probable cause
If the MUT-
IIcan not also communicate with the systems other than the GDI system,
the diagnosis line circuit may be defective.
If the MUT-
IIcan not communication with only the GDI system and the auto-cruise
control system, the harness wire between the engine-ECU or engine-A/T-ECU
and the diagnosis connector, may be defective.
In addition, if the MUT-
IIcan not communication with only the auto-cruise control
system, the auto-cruise control switch may be defective.DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the auto-cruise control switch
DMalfunction of the throttle valve controller
DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
NORefer to GROUP 13A - Troubleshooting (Inspection procedure 2).
Can the MUT-
IIcommunicate with the other systems (except the
GDI system)?NORefer to GROUP 13A - Troubleshooting (Inspection procedure 1).
YES
Can the MUT-
IIcommunicate with the GDI system?
YES
Check the auto-cruise control switch input signal.
(Refer to Inspection Procedure 9, P.17-19.)


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-16
Inspection Procedure 2
Even if brake pedal is depressed, auto-cruise control is
not cancelled.
Probable cause
The cause is probably a malfunction of stoplampswitch or a malfunction of stop
lampcircuit.DMalfunction of the stoplampswitch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
RepairIs the stoplampswitch installed correctly?NO
YES
Follow the INSPECTIONPROCEDURE FOR DIAGNOSIS CODE
No. 22 - Stoplampswitch system (Refer to P.17-11.)
Inspection Procedure 3
Even if clutch pedal is depressed, auto-cruise control is
not cancelled.
Probable cause
The cause is probably a malfunction of clutch switch or clutch switch circuit.DMalfunction of the clutch switch
DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
Clutch switch check (Refer to GROUP 21.)NG
Replace
OK
Measure at clutch switch connector D-137.
DDisconnect the connector and measure at the harness side.
DContinuity between terminal 1 and body earth
OK:ContinuityNGCheck the following connector:D-137
NG
Repair OK
Check trouble symptom.
OK
Check trouble symptom.
OK
Check the following connectors:
D-11, E-10, D-26, D-137
D-11, E-10, D-124, D-137 NG
RepairNG
Check the harness between the clutch switch and body earth,
and repair if necessary.
NG
Check the harness between the throttle valve controller and clutch
switch.
NG
Replace the throttle valve controller. OKCheck trouble symptom.NG
Repair


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-17
Inspection Procedure 4
Even if select lever is set to N range, auto-cruise control
is not cancelled.
Probable cause
The cause is probably a defective inhibitor switch circuit.DMalfunction of the connector
DMalfunction of the harness
DMalfunction of the throttle valve controller
OK
Check trouble symptom.
Check the following connector:D-11, E-113, C-05NG
Repair
NG
Check the harness between the throttle valve controller and inhibitor
switch.
NG
Replace the throttle valve controller. OKCheck trouble symptom.NG
Repair
Inspection Procedure 5
Even if auto-cruise control CANCEL switch is set to ON,
auto-cruise control is not cancelled.
Probable cause
The cause is probably an open-circuit in the circuit inside the CANCEL switch.DMalfunction of the auto-cruise control switch
Replace the auto-cruise control switch.
Inspection Procedure 6
Auto-cruise control cannot be set.
Probable cause
The cause is probably that the fail-safe function is cancelling auto-cruise control.
In this case, the MUT-
IIcan be used to check the trouble symptoms in each system
by inspecting the diagnosis codes.
The MUT-
IIcan also be used to check if the circuits of each input switch are normal
or not by inspecting the data list.DMalfunction of the auto-cruise control switch
DMalfunction of the harnesses
DMalfunction of the connectors
DMalfunction of the throttle valve controller
DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
Check trouble symptoms.
Can the auto-cruise control system communicate with the MUT-
II?NOFollow inspection procedure for trouble symptom No.1.
(Refer to P.17-15.)
YES
MUT-
IISelf-Diag code
(1) Is a diagnosis code regarding the auto-cruise control
system output?
(2) Is a diagnosis code regarding the GDI system output?(1) YESINSPECTION CHART FOR DIAGNOSIS CODES (Refer to
P.17-10.)
NO
MUT-
IIData list
02 SET switchNGCheck the control switch input system. (Inspection procedure 9,
P.17-19.)
OK
MUT-
IIData list
07 Clutch switch or inhibitor switch
NG
NO
Replace the throttle valve controller.(2) YES
Carry out the troubleshooting regarding the GDI system. (Refer
to GROUP 13A.)
Follow inspection procedures for trouble symptom Nos. 3 or 4.
(Refer to P.17-16, 17.) NG
Replace the engine-ECU or engine-A/T-ECU


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ENGINE AND EMISSION CONTROL -Auto-cruise Control System17-18
Inspection Procedure 7
Hunting (repeated acceleration and deceleration) occurs
at the set vehicle speed.
Probable cause
The cause is probably a malfunction of vehicle speed sensor or throttle control servo.
In either case, a diagnosis code regarding the GDI system must be confirmed.DMalfunction of the vehicle speed sensor
DMalfunction of the throttle control servo
DMalfunction of the throttle valve controller
DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
MUT-II Self-Diag code
Is a diagnosis code regarding the GDI system output?YES
NO
Replace the throttle valve controller.
Check trouble symptoms.NGReplace the engine-ECU or engine-A/T-ECU
Follow the troubleshooting regarding the GDI system. (Refer to
GROUP 13A.)
Inspection Procedure 8
When the MAIN switch of the auto-cruise control switch is
turned on, the auto-cruise control indicator lamp does not
illuminate. (However, the auto-cruise control in normal.)
Probable cause
There may be a burnt-out bulb or a malfunction of the auto-cruise control indicator
lampcircuit.DBurnt-out bulb
DMalfunction of the harness
DMalfunction of the connector
DMalfunction of the engine-ECU
DMalfunction of the engine-A/T-ECU
OK
Auto-cruise control indicatorlamp bulbcheckNG
Replace
NG
Repair
OK
NG
OK
Check trouble symptom.
NG
Check the harness between the J/B and the combination meter,
and repair if necessary.
Check the following connectors:
D-02, E-10, D-116
D-02, E-10, D-119
OK
Check trouble symptom.
NG
Repair
NG
Replace the engine-ECU or engine-A/T-ECU NG
Measure at the engine-ECU connector D-116 or engine-
A/T-ECU connector D-119 .
DDisconnect the connector and measure at the harness side.
DIgnition switch and auto-cruise control MAIN switch: ON
DVoltage between terminal 28 and earth or
voltage between terminal 15 and earth
OK:System voltage
Measure at the combination meter connector D-01.
DDisconnect the connector and measure at the harness side.
DIgnition switch and MAIN switch: ON
DVoltage between terminal 62 and earth
OK:System voltageCheck the following connector:D-01
NG
Check the harness between the combination meter and the engine-
ECU or engine-A/T-ECU , and repair if necessary. OK
Check trouble symptom.


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