Mitsubishi 380. Manual - part 430

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-260

STEP 12. Check the shift switch assembly.
Refer to 

P.23A-303

, Transmission Control.

Q: Is the switch operating properly?

YES : Go to Step 13.
NO :  Replace the shift switch assembly. Refer to 

P.23A-302

, Transmission Control.

STEP 13. Measure the switch output voltage at A/T-ECU 
connector B-19 by using check harness special tool 
MB992045.
(1) Disconnect all the connectors from the A/T-ECU.

(2) Connect special tool MB992045 (check harness) between 

the A/T-ECU and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.
(4) Move the selector lever to the sport mode.

(5) Measure the voltage between connector B-19 terminal 17 

and ground.

• The voltage should measure battery positive voltage.

(6) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage battery positive voltage?

YES : Go to Step 16.
NO :  Go to Step 14.

10DB125A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTOR:  B-19

10DB161A

A/T-ECU CHECK HARNESS
    MB992045

A/T-ECU

A/T-ECU CHECK 
HARNESS
CONNECTORS

10DB128A

B-19 HARNESS 

CONNECTOR: 

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-261

STEP 14. Check A/T-ECU connector B-19 and shift switch 
assembly connector D-14 for loose, corroded or damaged 
terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?

YES : Go to Step 15.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

10DB125A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTOR:  B-19

10DB093A

CONNECTOR:  D-14

FLOOR

WIRING

HARNESS

4

Y

2

15

ROOF

WIRING

HARNESS

D-14

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-262

STEP 15. Check the harness for open circuit or short 
circuit to ground between A/T-ECU connector B-19 
terminal 17 and shift switch assembly connector D-14 
terminal 6.
Q: Is the harness wire in good condition?

YES : Go to Step 4.
NO :  Repair or replace the harness wire.

STEP 16. Check A/T-ECU connector B-19 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Are the connector and terminals in good condition?

YES : Go to Step 4.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

10DB125A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTOR:  B-19

10DB093A

CONNECTOR:  D-14

FLOOR

WIRING

HARNESS

4

Y

2

15

ROOF

WIRING

HARNESS

D-14

16DB564A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTORS:  B-19, B-22

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-263

STEP 17. Check the shift switch assembly.
Refer to 

P.23A-303

, Transmission Control.

Q: Is the switch operating properly?

YES : Go to Step 18.
NO :  Replace the shift switch assembly. Refer to 

P.23A-302

, Transmission Control.

STEP 18. Measure the switch output voltage at A/T-ECU 
connector B-19 by using check harness special tool 
MB992045.
(1) Disconnect all the connectors from the A/T-ECU.

(2) Connect special tool MB992045 (check harness) between 

the A/T-ECU and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.

(4) Measure the voltage between connector B-19 terminal 8 

and ground.

• The voltage should measure battery positive voltage 

when the selector lever is upshift and hold.

(5) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage battery positive voltage?

YES : Go to Step 21.
NO :  Go to Step 19.

16DB564A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTORS:  B-19, B-22

10DB161A

A/T-ECU CHECK HARNESS
    MB992045

A/T-ECU

A/T-ECU CHECK 
HARNESS
CONNECTORS

10DB129A

B-19 HARNESS 

CONNECTOR: