Mitsubishi Eclipse. Manual - part 830

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-329

STEP 1. Using scan tool MB991958, check actuator test 
item 06: Torque Converter Clutch Solenoid Valve.

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958. 
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to actuator test mode for item 06: 

Torque Converter Clutch Solenoid Valve.

• An audible clicking or buzzing should be heard when the 

torque converter clutch solenoid valve is energized.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid valve operating properly?

YES : Go to Step 2.
NO :  Repair or replace the torque converter clutch solenoid 

valve. Refer to GROUP 23B, Valve Body 

P.23B-74

. 

Then confirm that the symptom is eliminated.

STEP 2. Check the vibration.
Q: Does the vibration occur when the transmission fluid 

temperature sensor connector has been disconnected?
YES : Check the engine system. Refer to GROUP 13A 

<2.4L Engine>, Diagnosis 

− Symptom Chart − Driving 

P.13A-28

, or GROUP 13B <3.0L Engine>, Diagnosis 

− Symptom Chart − Driving 

P.13B-27

. If the 

inspection result is not good, diagnose, repair, and/or 
replace the engine component(s).

NO :  Go to Step 3.

STEP 3. Check the torque converter hydraulic pressure.
Measure the torque converter hydraulic pressure. Then check if 
the torque converter hydraulic pressure is within the standard 
value. Refer to 

P.23A-28

, Hydraulic Pressure Test.

Q: Is the torque converter hydraulic pressure within the 

standard value?
YES : Go to Step 4.
NO :  Go to Step 5.

AC303127

AB

MB991911

16-PIN

MB991827

MB991824 

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-330

STEP 4. Replace the torque converter assembly.
(1) Remove the transaxle.
(2) Replace the torque converter assembly. Refer to GROUP 

23B, Transaxle 

P.23B-10

. Then check the symptom.

Q: Is the symptom eliminated?

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

STEP 5. Disassemble and clean the valve body.
Check the O-ring installation bolts for looseness and the valve 
body for damage. Repair or replace the faulty parts. Refer to 
GROUP 23B, Valve Body 

P.23B-74

.

Replace the valve body assembly if the damages are thought 
to be irreparable. Then check the symptom.
Q: Is the symptom eliminated?

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

STEP 6. Replace the PCM.
Q: Is the symptom eliminated?

YES : The procedure is complete.
NO :  Start over at Step 1.

AC001857

AC001860 AB

VALVE
BODY
ASSEMBLY

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-331

INSPECTION PROCEDURE 15: Vehicle Shifts Differently with A/C Engaged

AC102733AB

Dual Pressure Switch System Circuit

AC004374

CONNECTOR: A-36

AC

A-36

AC001741

CONNECTOR: C-12

AT

C-12

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-332

.

CIRCUIT OPERATION

• When the A/C is turned ON and the dual pres-

sure switch is closed, PCM (terminal number 83) 
receives battery voltage and then determines the 
A/C compressor has been signaled to engage.

• When the A/C compressor is engaged, the PCM 

increases line pressure and briefly delays shift 
points to compensate for the additional engine 
load.

.

COMMENT
The cause is probably a faulty dual pressure switch 
circuit or a defective PCM.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this case:)

• Malfunction of the dual pressure switch

• Damaged harness, connector

• Malfunction of A/C system

• Malfunction of the PCM

DIAGNOSIS

Required Special Tool:

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

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

AC106611AB

CONNECTOR: C-28

C-28

AC106628

CONNECTOR: C-94

AB

CONNECTOR BLOCK (RH)

C-94

AC001657

CONNECTOR: C-57 <2.4L ENGINE> OR 
C-59 <3.0L ENGINE>

AZ

PCM

C-57 <2.4L ENGINE> OR C-59 <3.0L ENGINE>