Mitsubishi Montero (2002-2004). Manual - part 938

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

23Ac-235

STEP 4. Check A/T control solenoid valve assembly 
connector C-03 and PCM connector D-136 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Are the connectors and terminals in good condition?

YES : Replace the torque converter clutch solenoid valve. 

Refer to GROUP 23B, Valve Body 

P.23B-80

.

NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-

2

.

AC204395

CONNECTOR : C-03

AE

C-03 (B)

6

10

4

9

5

3

8

2

7

1

AC204681AD

CONNECTOR: D-136

D-136 (GR)

121 122

123

124

125 126 127 128 129 130

131 132

133

134 135

136 137 138

139 140

141

142 143

144

145

146

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

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STEP 5. Using scan tool MB991502, check data list item 52: 
Amount of Torque Converter Clutch Slippage. (Second 
check)
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at constant speed of 60 km/h (37 

mph). (Gear range: 3rd gear)

(3) Set scan tool MB991502 to data reading mode for item 52, 

Amount of Torque Converter Clutch Slippage.

• Driving at constant speed of 60 km/h (31 mph), the dis-

play should be "

−10 to 10 r/min."

• If the accelerator pedal is released, the display on the 

scan tool changes. (50 km/h (31 mph) and less).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the torque converter clutch slippage within the 

specified range?
YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use Troubleshooting/
Inspection Service Points 

− How to Cope with 

Intermittent Malfunction 

P.00-6

.

NO :  Go to Step 6.

STEP 6. Replace the PCM.
(1) Replace the PCM.
(2) Test drive the vehicle.
(3) Check for A/T diagnostic trouble code.
Q: Is DTC 53 set?

YES : Go to Step 7.
NO :  The procedure is complete.

STEP 7. Replace the valve body.
(1) Replace the valve body. Refer to GROUP 23B, 

Transmission 

P.23B-18

.

(2) Test drive the vehicle.
(3) Check for A/T diagnostic trouble code.
Q: Is DTC 53 set?

YES : Replace the Torque Converter. Refer to 

P.23Aa-37

, 

Transmission and Transfer Assembly.

NO :  The procedure is complete.

ACX01539AD

MB991502

16-PIN

ACX02161AD

VALVE BODY ASSEMBLY

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

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DTC 54: A/T Control Relay System

AC205196AB

AC204167

CONNECTOR : A-03

AT

A-03 (B)

6

12

5

3 4

2

1

9 10

8

7

11

AC204750

CONNECTOR : D-13

AB

PCM

1
3 4

2

DIAGNOSTIC TROUBLE CODE PROCEDURES <AUTOMATIC TRANSMISSION>

TSB Revision

DIAGNOSTIC TROUBLE CODE PROCEDURES

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.

CIRCUIT OPERATION

• A/T control relay (terminal 1) receives battery 

positive voltage through a battery.

• The PCM (terminal 127) applies voltage to ener-

gize the A/T control relay (terminal 4). With the A/
T control relay energized, system voltage is 
applied to the PCM (terminals 123 and 124).

.

DTC SET CONDITIONS
If the A/T control relay voltage is less than 7 volts at 
the PCM (terminals 123 and 124) when the ignition 
switch is in the "ON" position, DTC 54 is set. The 
transmission is locked into the 3rd gear as a fail-safe 
measure, and the "N" range light flashes once per 
second.

.

TROUBLESHOOTING HINTS (The most likely 
causes for this code to be set are:)

• Malfunction of the A/T control relay

• Damaged harness, connector

• Malfunction of the PCM

AC204171

CONNECTOR : D-14

AM

4

9

8

6

5

7

1 2

3

10

AC204681AD

CONNECTOR: D-136

D-136 (GR)

121 122

123

124

125 126 127 128 129 130

131 132

133

134 135

136 137 138

139 140

141

142 143

144

145

146