Mitsubishi Grandis. Manual - part 862

TROUBLESHOOTING <A/T>

AUTOMATIC TRANSMISSION (FF)

23A-115

STEP 22. Check the harness between shift switch
assembly connector C-121 terminal No.5 and
engine-A/T-ECU connector C-112 terminal No.68.

Check the output line for short-circuited or open
circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

AC310613

C-121

Connector: C-121
<LHD>

Harness side

AC310631AW

C-121

Harness side

Connector: C-121
<RHD>

AC311284

Connector: C-112 <LHD>

Connector: C-112 <RHD>

Harness side

Engine-A/T-ECU

C-112 (GR)

Engine-A/T-ECU

TROUBLESHOOTING <A/T>

AUTOMATIC TRANSMISSION (FF)

23A-116

INSPECTION PROCEDURE 17: Abnormal shift indicator display

OPERATION

The engine-A/T-ECU detects the shift range (sport
mode) which the driver has selected, and sends the
information to the combination meter.

COMMENTS ON TROUBLE SYMPTOM

Connector(s) or wiring harness in the CAN bus lines
between the engine-A/T-ECU and the combination
meter, the power supply system to the
engine-A/T-ECU, the combination meter, or the
engine-A/T-ECU may be defective.

Possible causes

• The communication line is defective.

• Malfunction of shift switch assembly

• Malfunction of the combination meter

• Malfunction of the engine-A/T-ECU

DIAGNOSIS

STEP 1. MUT-III diagnosis code

Either of diagnosis codes 27 or 28 is set, inhibitor
switch is defective.

Q: Are diagnosis codes 27 or 28 output?

COMBINATION
METER

ENGINE-
A/T-ECU

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Gray R : Red P : Pink V : Violet

Communication circuit (CAN communication line) between engine-A/T-ECU and combination meter

TROUBLESHOOTING <A/T>

AUTOMATIC TRANSMISSION (FF)

23A-117

YES <diagnosis code 27 is set> :

Refer to

diagnosis code 27: Inhibitor switch system

P.23A-52

YES <diagnosis code 28 is set> :

Refer to

diagnosis code 28: Inhibitor switch system

P.23A-59

NO :

Go to Step 2.

STEP 2. MUT-III data list

• Item 67: Select switch

• Item 68: Upshift switch

• Item 69: Downshift switch

Check the above data list. (Refer to data list
reference table

P.23A-117

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Refer to inspection procedure 16: shift
switch assembly system

P.23A-100

STEP 3. MUT-III CAN bus diagnostics

Use the MUT-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the CAN bus lines.(Refer to G.54D

−

Diagnosis

P.54D-16

)

STEP 4. MUT-III actuator test

Execute combination meter actuator test.

• Item A2: All shift position indicator lamps

illuminate.

• Item A3: All shift position indicator lamps go out.

OK: All shift position indicator lamps
illuminate or go out.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Replace the combination meter.

STEP 5. Replace the engine-A/T-ECU.

Replace the engine-A/T-ECU and check the trouble
symptom.

Q: Is the check result normal?

YES :

The inspection is complete.

NO :

Replace the combination meter.

DATA LIST REFERENCE TABLE

M1231008100393

Data list
No.

Check item

Inspection conditions

Normal condition

0000

Crank angle sensor

Engine: Idling
Selector lever

position: P

Compare the engine
speeds displayed on the
tachometer and the
MUT-III.

Identical

0001

Input shaft speed
sensor

Driving at a constant speed of 50 km/h in 3rd

1,800

− 2,100 r/min

0002

Output shaft speed
sensor

Driving at a constant speed of 50 km/h in 3rd

1,800

− 2,100 r/min

TPS

Ignition switch: ON
Engine: Stopped

Accelerator pedal: Fully
closed

300

− 700 mV

Accelerator pedal:
Depressed

Gradually increases
from the above value.

Accelerator pedal: Fully
open

4,000 mV or more

A/T fluid temperature
sensor

Driving after engine has warmed up

Gradually increases.

Stop lamp switch

Brake pedal: Depressed

Brake pedal: Released

OFF

Vehicle speed signal Idling in 1st (Vehicle stopped)

0 km/h

Driving at a constant speed of 50 km/h in 3rd

50 km/h

TROUBLESHOOTING <A/T>

AUTOMATIC TRANSMISSION (FF)

23A-118

LR solenoid valve
duty ratio

Driving at a constant speed of 10 km/h in 1st

0 %

Driving at a constant speed of 20 km/h in 2nd

100 %

Driving at a constant speed of 30 km/h in 3rd

100 %

Driving at a constant speed of 50 km/h in 4th

100 %

UD solenoid valve
duty ratio

Driving at a constant speed of 10 km/h in 1st

0 %

Driving at a constant speed of 20 km/h in 2nd

0 %

Driving at a constant speed of 30 km/h in 3rd

0 %

Driving at a constant speed of 50 km/h in 4th

100 %

2ND solenoid valve
duty ratio

Driving at a constant speed of 10 km/h in 1st

100 %

Driving at a constant speed of 20 km/h in 2nd

0 %

Driving at a constant speed of 30 km/h in 3rd

100 %

Driving at a constant speed of 50 km/h in 4th

0 %

OD solenoid valve
duty ratio

Driving at a constant speed of 10 km/h in 1st

100 %

Driving at a constant speed of 20 km/h in 2nd

100 %

Driving at a constant speed of 30 km/h in 3rd

0 %

Driving at a constant speed of 50 km/h in 4th

0 %

DCC solenoid valve
duty ratio

Driving at a constant speed 60 km/h in 3rd gear

− 99.6 %

Driving at 60 km/h in 3rd gear, then fully close
the accelerator pedal

− 99.6 % to 0 %

INVECS-II cancel
command

INVECS-II activated

INVECS-II not activated

OFF

Damper clutch
amount of slippage

Driving at a constant speed 60 km/h in 3rd gear

−10 to 10 r/min

Driving at 60 km/h in 3rd gear, then fully close
the accelerator pedal

The value changes
from the above value.

A/T control relay
output voltage

Ignition switch: ON

System voltage

Engine intake
manifold negative
pressure

Engine: Idling
Selector lever

position: N, P

Accelerator pedal: fully
closed to depressed

Data changes

Inhibitor switch

Ignition switch: ON
Engine: Stopped

Selector lever position: P

Selector lever position: R

Selector lever position: N

Selector lever position: D

Data list
No.

Check item

Inspection conditions

Normal condition

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