Mitsubishi Montero (2004+). Manual - part 929

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-291

STEP 16. Measure the A/T control relay output voltage at 
PCM connector D-136 by backprobing.
(1) Do not disconnect connector D-136.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 123 and ground by 

backprobing.

• The measured voltage should equal battery positive 

voltage.

(4) Measure the voltage between terminal 124 and ground by 

backprobing.

• The measured voltage should equal battery positive 

voltage.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage equal to battery positive 

voltage between terminal 123 and ground, and between 
terminal 124 and ground?
YES : Go to Step 19.
NO :  Go to Step 17.

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

AC204918

AC204918 BS

D-136 HARNESS CONNECTOR : 
HARNESS SIDE

138

131

132 133

145

140

146

141

139

124

123

142

134

125 126 127 128 129 130

137

144

136

143

135

122

121

AC204918 BT

D-136 HARNESS CONNECTOR : 
HARNESS SIDE

138

131

132 133

145

140

146

141

139

124

123

142

134

125 126 127 128 129 130

137

144

136

143

135

122

121

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-292

STEP 17. Check 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 : Go to Step 18.
NO :  Repair or replace the damaged components. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

.

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

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-293

STEP 18. Check harness for open circuit or short circuit to 
ground between A/T control relay connector D-13 terminal 
3 and PCM connector D-136 terminals 123, 124.
Q: Is the harness wire in good condition?

YES : Go to Step 19.
NO :  Repair or replace the harness wire.

AC204750

CONNECTOR : D-13

AB

PCM

1
3 4

2

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

AUTOMATIC TRANSMISSION DIAGNOSIS

TSB Revision

AUTOMATIC TRANSMISSION

23A-294

STEP 19. Using scan tool MB991958, check data list item 
54: A/T control relay output Voltage.

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 the data reading mode.

• Item 54: 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 to battery positive 

voltage?
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 :  Replace the PCM.

AC307591 AC

MB991911

MB991824

MB991827

AC307591

DATA LINK

CONNECTOR