Mitsubishi L200. Manual - part 174

TROUBLESHOOTING

DIESEL FUEL

13A-492

YES : 

Replace the engine-ECU. When the engine-

ECU is replaced, write the chassis number 
(Refer to GROUP 00 

− Precautions Before 

Service 

− How to Perform Chassis Number 

Writing ). After replacing the engine-ECU, 
register the injector identification code and 
learn fuel injection (Refer to GROUP 00 

− 

Precautions Before Service 

− What The 

Common Rail Engine Learns ). After 
registering the injector identification code, 
the vehicle equipped with the DPF carries 
out the forcible DPF regeneration. (Refer to 
GROUP 17 

− Emission Control − Diesel 

Particulate Filter (DPF) System 

− Forcible 

DPF Regeneration ).

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use Troubleshooting/

Inspection Service Points 

− How to Cope 

with Intermittent Malfunction ).

Inspection Procedure 17: Engine-ECU Battery Back-up System

OPERATION

• Backup power source is directly supplied to an 

engine-ECU from a battery.

AKA00116

101 102

103104 105 106107 108109 110 111112 113 114115

118119 120 121122 123124 125126127 128 129130

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146147 148 149150 151152 153154155 156 157158

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C-103

10

20A

Fusible link

103

Battery
backup

3

A-115

Relay 
box

W-R

W-B

W-B

Battery back-up circuit

Wire colour code
B: Black  LG: Light green  G: Green  L: Blue  W: White  Y: Yellow  SB: Sky blue  BR: Brown  O: Orange  GR: Grey
R: Red  P: Pink  V: Violet  PU: Purple  SI: Silver

Engine-ECU

23

AB

TROUBLESHOOTING

DIESEL FUEL

13A-493

PROBABLE CAUSES

• Damaged harness (Open circuit between engine-

ECU and relay box)

• Damaged connector (Engine-ECU connector)

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check battery voltage.

• Measure battery voltage during cranking.

OK: 8 V or more

Q: Is the check result normal?

YES : 

Go to Step 2 .

NO : 

Check battery (Refer to GROUP 54A 

− 

Battery 

− On-vehicle Service − Battery test 

).

STEP 2. Perform voltage measurement at C-103 
engine-ECU connector.

• Disconnect connector, and measure at harness 

side.

• Voltage between terminal No. 103 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 5 .

NO : 

Go to Step 3 .

STEP 3. Connector check: C-103 engine-ECU 
connector and A-115 intermediate connector.

Q: Are the check results normal?

YES : 

Go to Step 4 .

NO : 

Repair or replace.

AKA00090

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C-103 (B)

C-103 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-103

AB

AKA00090

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C-103 (B)

C-103 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-103

AB

AK700922

1 2

3

6 7 8

4

5

9 10

AB

A-115

Harness side connector

A-115

Connector: A-115

<L.H. drive vehicles>

<R.H. drive vehicles>

TROUBLESHOOTING

DIESEL FUEL

13A-494

STEP 4. Check for open circuit between C-103 
(terminal No. 103) engine-ECU connector and A-
115 (terminal No. 3) intermediate connector.

• Disconnect connector.

Q: Is the check result normal?

YES : 

Go to Step 5 .

NO : 

Repair the harness wire.

STEP 5. Check the trouble symptoms.

Q: Does trouble symptom persist?

YES : 

Replace the engine-ECU. When the engine-

ECU is replaced, write the chassis number 
(Refer to GROUP 00 

− Precautions Before 

Service 

− How to Perform Chassis Number 

Writing ). After replacing the engine-ECU, 
register the injector identification code and 
learn fuel injection (Refer to GROUP 00 

− 

Precautions Before Service 

− What The 

Common Rail Engine Learns ). After 
registering the injector identification code, 
the vehicle equipped with the DPF carries 
out the forcible DPF regeneration. (Refer to 
GROUP 17 

− Emission Control − Diesel 

Particulate Filter (DPF) System 

− Forcible 

DPF Regeneration ).

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use Troubleshooting/

Inspection Service Points 

− How to Cope 

with Intermittent Malfunction ).

AKA00090

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C-103 (B)

C-103 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-103

AB

AK700922

1 2

3

6 7 8

4

5

9 10

AB

A-115

Harness side connector

A-115

Connector: A-115

<L.H. drive vehicles>

<R.H. drive vehicles>

TROUBLESHOOTING

DIESEL FUEL

13A-495

Inspection Procedure 18: 1st and 2nd Rail Switch System <M/T>

OPERATION

• The 1st and 2nd rail switches detect that a trans-

mission is shifted into the 1st speed gear posi-
tion.

• An engine-ECU controls an engine speed to be 3, 

000 r/min or less so that an excessive load can-
not be applied to a drive train system due to a 
sudden start in the first gear position.

PROBABLE CAUSES

• Failed 1st and 2nd rail switch

AKB00289

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43 44 45 46 47 48

73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

2

1

Ignition switch (IG1)

11

L-B

L-Y

L-Y

G-Y

G-Y

G-Y

1st and 2nd Rail Switch Circuit

Wire colour code
B: Black  LG: Light green  G: Green  L: Blue  W: White  Y: Yellow  SB: Sky blue  BR: Brown  O: Orange  GR: Grey
R: Red  P: Pink  V: Violet  PU: Purple  SI: Silver

Engine-ECU

1st and 2nd rail switch

21

7.5A

2

J/B

C-208

C-207

4

C-30

10

1

C-29

2

4

A-115

6

OFF

ON

C-105

B-06

MU802662

AC