Mitsubishi 380. Manual — part 419

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-216

STEP 14. Check harness for open circuit or short circuit to
ground between A/T control relay connector B-16X
terminal 3 in the engine component relay box and A/T-ECU
connector B-22 terminal 4.
Q: Is the harness wire in good condition?

YES : Go to Step 15.
NO : Repair or replace the harness wire.

10DB098A

RELAY BOX

CONNECTOR: B-16X

2

1

3 4

FRONT OF
VEHICLE

16DB564A

COVER

AIR

CLEANER

A/T

CONTROL

UNIT

CONNECTORS: B-19, B-22

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-217

STEP 15. Using diagnostic tool MB991958, check A/T data
list item 8: A/T control relay output Voltage.

CAUTION

To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958 to the data link

connector.

(2) Turn the ignition switch to the "ON" position.
(3) Set diagnostic tool MB991958 to the data reading mode.

• Item 8: A/T Control Relay Output Voltage.

• The voltage should equal battery positive voltage.

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

Q: Is the measured voltage equal battery positive voltage?

YES : It can be that this malfunction is intermittent. Refer to

GROUP 00, How to Use Troubleshooting/Inspection
Service Points

− How to Cope with Intermittent

Malfunction

P.00-14

.

NO : Replace the A/T-ECU.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-218

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Engine does not Crank

.

COMMENT

If the engine does not crank when the selector lever
is placed in the "P" or "N" position, the cause is prob-
ably a malfunction of the transmission inhibitor
switch system, transmission control cable assembly,
engine system, torque converter or transmission oil
pump.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CONDITION:)

• Malfunction of the transmission inhibitor switch

• Malfunction of the transmission control cable

assembly

• Malfunction of the engine system

• Malfunction of the torque converter

• Malfunction of the transmission oil pump
• Check RED brake system.

Circuit drawings

• Refer to circuit diagrams GROUP-

90

• Refer to configuration diagrams GROUP-

80

• Refer to component locations GROUP-

70

DIAGNOSIS

Required Special Tool:

• MB991958: Diagnostic Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A

STEP 1. Using diagnostic tool MB991958, read the A/T
diagnostic trouble code.

CAUTION

To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958 to the data link

connector.

(2) Turn the ignition switch to the "ON" position.
(3) Check for A/T diagnostic trouble code.
(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is A/T DTC "(P0705)" set?

YES <(P0705) set> : Refer to

P.23A-97

: Transmission

Inhibitor Switch System (Open Circuit) or refer to

P.23A-119

: Transmission Inhibitor Switch System

(Short Circuit).

NO : Go to Step 2.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTOMATIC TRANSMISSION DIAGNOSIS

AUTOMATIC TRANSMISSION

23A-219

STEP 2. Check the transmission control cable assembly.
Move the selector lever to each position. The manual control
lever position of the transmission inhibitor switch should match
the transmission range.

Q: Is the manual control lever position correct?

YES : Go to Step 3.
NO : Repair the transmission control cable. Refer to

P.23A-299

, Transmission Inhibitor Switch and Control

Cable Adjustment. Retest the system to verify the
repair.

STEP 3. Check the engine system.
Refer to GROUP 13A, Diagnosis

− Trouble Symptom Chart −

Starting

13A-21

.

Q: Is the inspection result good?

YES : Go to Step 4.
NO : Repair or replace the appropriate engine

components.

STEP 4. Check the torque converter.
(1) Remove the starter.
(2) Turn the torque converter and check for a binding or

sticking condition. Check the ring gear for damaged or
missing teeth.

NOTE: Since the torque converter drives the oil pump, turn-
ing the torque converter also check for a binding oil pump. If
either of these components are damaged the transmission
will need to be removed for inspection.

Q: Does the torque converter turn freely without any

missing or damaged teeth?
YES : Go to Step 5.
NO : Replace the torque converter. Refer to GROUP 23B,

Transmission

P.23B-13

.

STEP 5. Repair or replace the starter.

Q: Is the symptom eliminated?

YES : The procedure is complete.
NO : Go to Step 6.

10DB163A

P

R

N

D

<F5A5A>

AC001857