2000 MITSUBISHI MONTERO ECU

AUTOMATIC TRANSMISSION -Troubleshooting 23-56
Inspection procedure 12
Some points (incorrect shift points)
Probable cause
If some of the shift points are incorrect while driving, the cause is probably a
malfunction of the valve body, or it is a characteristic of control and is not a
malfunction.DMalfunction of valve body
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
LRefer to the Transmission Workshop Manual.
INVECS-
IIcancel command
DCancels INVECS-
IIusing MUT-
II.
YES
Problem is a characteristic of control
and is not a malfunction. YES
Is standard shifting normal?NODoes the problem occur when the
ATF temperature is less than 35
°C
or higher than 120
°C?NODisassemble, clean and re-assemble
the valve body.
L
DMake sure that the mounting
bolts are not loose and that the
O-ring and valve body are not
damaged or positionedincorrectly.
DIf the extent of thedamagelooks
too bad for repairs to be carried
out, replace the valve body
assembly.
Check the trouble symptoms.
Replace the engine-A/T-ECU or
A/T-ECU.NG
Inspection procedure 13
No diagnosis code (no shifting)
Probable cause
No shifting during driving
However, if a diagnosis code is not output, the cause is probably malfunction of
the inhibitor switch system, the shift switch assembly, theengine A/T-ECU or
the A/T-ECU.DMalfunction of Inhibitor switch
DMalfunction of shift switch assembly system
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
Does the transmission stay at 3rd in
D range?NOMUT-
IIData List
DNo. 61 Inhibitor switch
OK:The ECU input signal and
the selector lever position
should correspond.NGInspection Procedure 16: Inhibitor
switch system check (Refer to
P.23-58.)
YES
OK
NG
Inspection Procedure 17: Shift switch
assembly system check (Refer to
P.23-58.)
NO
Power supply circuit check
DCheck for anopencircuit in the
harness, a poor connector
connection or a blown fuse wire.
DIf there is a blown fuse, check
for whatever caused the blown
fuse and replace the problem
part.
YES
Replace the engine-A/T-ECU or
A/T-ECU.
MUT-
IIData List
DNo.67 Select switch
DNo.68 Shift switch (UP)
DNo.69 Shift switch (DOWN)
OK:The ECU input signal and
the selector lever position
should correspond.
Check the trouble symptoms.OK
NG
YES
Is powerbeing supplied to the
A/T-ECU or to the
engine-A/T-ECU? NO
Is the backup power supplybeing
supplied to the A/T-ECU or to the
engine-A/T-ECU?


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting 23-57
Inspection procedure 14
Poor acceleration
Probable cause
If the vehicle does not accelerate after downshifting, the cause is probably a
malfunction of the enginesystem or of a brake or clutch.DMalfunction of enginesystem
DMalfunction of brake or clutch
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
LRefer to the Transmission Workshop Manual.
Engine system check
DControl system, ignition system, fuel system, vehicle bodyNG
Repair or replace
OK
Brake and clutch check
L
DCheck for a problem such as burnt facing, poor piston
sealing or interference with the retainer.Check the trouble symptoms.
Replace the engine-A/T-ECU or A/T-ECU.NG
Inspection procedure 15
Vibration
Probable cause
If vibration occurs when accelerating or decelerating while driving at a constant
speed or driving in top range, the cause is probably abnormal damper clutch
pressure, or a malfunction of theenginesystem, DCC solenoid valve, torque
converter or valve body.DAbnormal damper clutch pressure
DMalfunction of enginesystem
DMalfunction of DCC solenoid valve
DMalfunction of torque converter
DMalfunction of valve body
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
LRefer to the Transmission Workshop Manual.
NGReplace the DCC solenoid valve.
L
OK
Does the problem still occur when theengine coolant
temperature sensor is disconnected?YESEngine system check
DControl system, ignition system, fuel system, vehicle body
NO
Fluid pressure test (Refer to P.23-106.)
DMeasure the damper clutch fluid pressure.
Standard value:Refer to P.23-106.NGDisassemble, clean and re-assemble the valve body.
L
DMake sure that the mounting bolts are not loose and that
the O-ring and valve body are notdamaged or positioned
incorrectly.
DIf the extent of thedamagelooks too bad for repairs to be
carried out, replace the valve body assembly.
OK
Replace the torque converter assembly.Check the trouble symptoms.
Replace the engine-A/T-ECU or A/T-ECU.OK
MUT-
IIActuator Test
DNo. 6 DCC solenoid valve
OK:Sound of operation can be heard


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting AUTOMATIC TRANSMISSION -Troubleshooting 23-58
Inspection procedure 16
Inhibitor switch system
Probable cause
The cause is probably a malfunction of the inhibitor switch circuit or the ignition
switch circuit.DMalfunction of Inhibitor switch
DMalfunction of ignition switch
DMalfunction of harness or connector
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
Inhibitor switch check (Refer to P.23-98.)NG
OK
Inhibitor switch connector C-05 voltage check
DDisconnect the connector and measure at the
harness side.
DVoltage between terminal 7 and earth
(Ignition switch: ON)
OK:System voltage
OKCheck the following connectors:D-208, D-213,
D-32, E-115, C-05NG
Repair
OK
Check the harness between the inhibitor switch
and the ignition switch.
OK
Check the trouble symptoms.
NGNG
Repair
Check the trouble symptoms.Replace
NG
Repair
Ignition switch check
NG
Repair
DCheck the harness between the inhibitor
switch and the engine-A/T-ECU. <6G7>
DCheck the harness between the inhibitor
switch and the A/T-ECU.<4M4>
OK
Replace the engine-A/T-ECU or A/T-ECU. NGNG
OK
Check the following connectors:<6G7> C-05,
E-113, D-128, D-122, <4M4>C-05, E-115, D-128,
B-109
Inspection procedure 17
Shift switch assembly system
Probable cause
The cause is probably a malfunction of the inhibitor switch circuit, shift switch
assembly circuit, or of the engine-A/T-ECU or A/T-ECU.DMalfunction of inhibitor switch
DMalfunction of select switch
DMalfunction of shift switch (UP)
DMalfunction of shift switch (DOWN)
DMalfunction of harness or connector
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
Inhibitor switch check (Refer to P.23-98.)NGInhibitor switch check
DInspection Procedure 16: Inhibitor switch system check
(Refer to P.23-58.)
OK
Shift switch assembly check (Refer to P.23-117.)NG
Replace
OK
DCheck the harness between the shift switch assembly and
the engine-A/T-ECU. <6G7>
DCheck the harness between the shift switch assembly and
the A/T-ECU.<4M4>NG
Repair
OK
Check the trouble symptoms.NGReplace the engine-A/T-ECU or A/T-ECU.
OK
Check the following connectors:<6G7> E-117, E-113,
D-122, <4M4> E-117, E-113,D-109NG
Repair


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting 23-59
Inspection procedure 18
Dual pressure switch system
Probable cause
The cause is probably a malfunction of thedualpressure switch circuit, or of the
engine-A/T-ECU or A/T-ECU.DMalfunction of dualpressure switch
DMalfunction of harness or connector
DMalfunction of A/C system
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
Dual pressure switch check
(Refer to GROUP 55 – On-Vehicle Service.)NG
Measure at engine-A/T-ECU connector D-121
<6G7> or at A/T-ECU connector D-107 <4M4>.
DDisconnect the connector and measure at the
harness side.
DIgnition switch: ON
DA/C switch: ON
D<6G7> Voltage between terminal 83 and earth
<4M4> Voltage between terminal 10 and
earth
OK:System voltage
OKCheck the following connectors:<6G7> D-121,
A-04,<4M4> D-107,A-04NG
Repair OK
Check the trouble symptoms.Replace
A/C system check (Refer to GROUP 55 -
Troubleshooting.)NG
Replace the engine-A/T-ECU or A/T-ECU. NG
Inspection procedure 19
Vehicle speed sensor system
Probable cause
The cause is probably a malfunction of the vehicle speed sensor circuit, or of
the A/T-ECU or the engine-A/T-ECU.DMalfunction of vehicle speed sensor
DMalfunction of connector
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
MUT-
IIData List
DNo.29 Vehicle speed sensor
OK:Refer to P.23-61 (Data List Chart).NO
Speedometer check
(Refer to GROUP 54A - Combination Meter.)
OK
OKNG NG
YES
Is the speedometer correct?
OK
Transient malfunction (Refer to GROUP 00 - Points to Note
for Transient Malfunctions.)
Check the trouble symptoms.
Replace the engine-A/T-ECU or A/T-ECU.NG
Check the following connectors:<6G7> C-09, E-113, E-13,
D-121<4M4>C-09, E-113, E-13, D-109
DCheck the harness between the engine-A/T-ECU and the
vehicle speed sensor. <6G7>
DCheck the harness between the A/T-ECU and the vehicle
speed sensor.<4M4>Repair
NG
Repair


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting 23-60
Inspection procedure 20
4LLc switch system
Probable cause
The cause is probably a malfunction of the 4LLc switch circuit, or of the
engine-A/T-ECU or A/T-ECU.DMalfunction of 4LLc switch
DMalfunction of harness or connector
DMalfunction of engine-A/T-ECU <6G7>
DMalfunction of A/T-ECU<4M4>
4LLc switch check (Refer to P.23-99.)NG
4LLc switch connector C-06 voltage check
DDisconnect the connector and measure at the
harness side.
DIgnition switch: ON
DVoltage between terminal 1 and earth
OKFSystem voltageCheck the following connectors:<6G7> C-06,
E-113, D-122, <4M4>C-06, E-113, D-107NG
Repair OK
Check the trouble symptoms.Replace
OKReplace the engine-A/T-ECU or A/T-ECU. NG
DCheck the harness between 4LLc switch and
the engine-A/T-ECU, and repair if necessary.
<6G7>
DCheck the harness between 4LLc switch and
the A/T-ECU, and repair if necessary.<4M4>
Check the following connector:C-06
NG
Repair
OK
NGOK


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting 23-67
Ter-
minal
No.Standard value Inspection conditions Check item
10A/C compressor load signalA/C switch: OFF0V
A/C switch: ONSystem voltage
11Power supplyIgnition switch: OFF0V
Ignition switch: ONSystem voltage
12EarthAt all times0V
13EarthAt all times0V
14OD solenoid valveEngine: Idling
Shift range: 3rdSystem voltage
Engine: Idling
Shift range: Park7-9V
15DCC solenoid valveEngine: Idling
Shift range: 1stSystem voltage
162nd solenoid valveEngine: Idling
Shift range: 2ndSystem voltage
Engine: Idling
Shift range: Park7-9V
172nd shift indicator lampShift range: 2ndSystem voltage
Shift range: Other than the above0V
184th shift indicator lampShift range: 4thSystem voltage
Shift range: Other than the above0V
24Power supplyIgnition switch: OFF0V
Ignition switch: ONSystem voltage
25EarthAt all times0V
26EarthAt all times0V
31Input shaft speed sensorMeasure between terminals (31) and (43) using an
oscilloscope.
Engine: 2 000 r/min
Shift range: 4thCheck Procedure
using an Oscillo-
scope (Refer to
P.23-69.)
32Output shaft speed sensorMeasure between terminals (32) and (43) using an
oscilloscope.
Engine: 2 000 r/min
Shift range: 4thCheck Procedure
using an Oscillo-
scope (Refer to
P.23-69.)
33Engine speed sensorEngine: Idling2.0 - 2.4 V
38Backup power supplyAt all timesSystem voltage
43Sensor earthAt all times0V
44A/T fluid temperature sensorA/T fluid temperature 20°C3.8 - 4.0 V
A/T fluid temperature 40°C3.2 - 3.4 V
A/T fluid temperature 80°C1.7 - 1.9 V
45Accelerator pedal positionAccelerator pedal: Fully closed (engine stopped)0.985 - 1.085 V
sensor (APS)Accelerator pedal: Fully open (engine stopped)4.0 V or higher
51RED solenoid valveEngine: Idling
Shift range: 5thSystem voltage
Engine: Idling
Shift range: Park7-9V
53Output communication withEngine: IdlingOther than 0 V
engine-ECUSelector lever position: D


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting 23-68
Ter-
minal
No.Standard value Inspection conditions Check item
54Input communication withEngine: IdlingOther than 0 V
engine-ECUSelector lever position: D
55Inhibitor switch PIgnition switch: ON
Selector lever position: PSystem voltage
Ignition switch: ON
Selector lever position: Other than the above0V
56Inhibitor switch NIgnition switch: ON
Selector lever position: NSystem voltage
Ignition switch: ON
Selector lever position: Other than the above0V
57Select switchIgnition switch: ON
Selector lever operation: Sports modeSystem voltage
Ignition switch: ON
Selector lever operation: Other than the above0V
58Downshift switchIgnition switch: ON
Selector lever position: Downshifted in Sports mode
and lever heldSystem voltage
Ignition switch: ON
Selector lever operation: Other than the above0V
59Stop lamp switchIgnition switch: ON
Brake pedal DepressedSystem voltage
Ignition switch: ON
Brake pedal Released0V
62DIR solenoid valveEngine: Idling
Shift range: ParkSystem voltage
Engine: Idling
Shift range: 2nd7-9V
65Wide open throttle switchAccelerator pedal: Released4.5 - 5.5 V
Accelerator pedal: DepressedLess than 0.4 V
66Inhibitor switch RIgnition switch: ON
Selector lever position: RSystem voltage
Ignition switch: ON
Selector lever position: Other than the above0V
67Inhibitor switch DIgnition switch: ON
Selector lever position: DSystem voltage
Ignition switch: ON
Selector lever position: Other than the above0V
68Upshift switchIgnition switch: ON
Selector lever position: Upshifted in Sports mode and
lever heldSystem voltage
Ignition switch: ON
Selector lever position: Other than the above0V
69Vehicle speed sensorWhen stopped0V
When starting to drive forward slowly.0 V and 5 V alter-
nates
71A/T control relayIgnition switch: OFF0V
Ignition switch: ON10 - 12 V
72EarthIgnition switch: ON0V


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk

AUTOMATIC TRANSMISSION -Troubleshooting II>23-71
Diagnosis
codeReference page Diagnosis item
35Freewheel engage switch systemOpen circuit/Short-cir-
cuit/Malfunction of
switch23-83
41Shift actuator (short-circuit/open circuit) systemOpen circuit/Short-cir-
cuit/Malfunction of ac-
tuator/Malfunction of
ECU23-84
42Shift actuator (short-circuit) systemShort-circuit/Malfunc-
tion of actuator/Mal-
function of ECU23-85
43Shift actuator (open circuit) systemOpen circuit/Malfunc-
tion of actuator/Mal-
function of ECU
44Shift actuator (overload) systemMalfunction of transfer
shift mechanism/Mal-
function of actuator23-86
45Tyre problemIncorrect tyre pres-
sure/Uneven tyre sizes23-86
51Malfunction of transfer-ECU23-86


www.WorkshopManuals.co.uk


Purchased from www.WorkshopManuals.co.uk