Mitsubishi L200. Manual - part 109

TROUBLESHOOTING

DIESEL FUEL

13A-232

STEP 5. Check harness between A-159 (terminal 
No. 1) No. 2 exhaust gas temperature sensor 
(catalyst temperature) connector and C-105 
(terminal No. 59) engine-ECU connector.

NOTE: Before checking harness, check intemediate 
connector A-28, and repair if necessary.

• Check output line for short circuit.

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Repair the damaged harness wire.

STEP 6. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13A-542

a. Item 118: No. 2 exhaust gas temperature sensor 

(catalyst temperature)

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use Troubleshooting/

Inspection Service Points 

− How to Cope 

with Intermittent Malfunctions ).

NO : 

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, 
carry out the forcible DPF regeneration. 
(Refer to GROUP 17 

− Emission Control − 

Diesel Particulate Filter (DPF) System 

− 

Forcible DPF Regeneration ).

1

2

AKB00272

A-159 (B)

Harness side
connector

Connector: A-159

No. 2 exhaust gas
temperature sensor
(catalyst temperature)

AB

AKA00089

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C-105 (B)

C-105 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-105

AB

TROUBLESHOOTING

DIESEL FUEL

13A-233

Code No. P0428: No. 2 Exhaust Gas Temperature Sensor (catalyst temperature) Circuit High Input 
<Euro5>

OPERATION

• A power voltage of 5 V is applied to the No. 2 

exhaust gas temperature sensor (catalyst tem-
perature) output terminal (terminal No. 1) from 
the engine-ECU (terminal No. 59).

• The power voltage is earthed to the engine-ECU 

(terminal No. 83) from the No. 2 exhaust gas tem-
perature sensor (catalyst temperature) (terminal 
No. 2).

FUNCTION

• The No. 2 exhaust gas temperature sensor (cata-

lyst temperature) converts the catalyst tempera-
ture into a voltage and inputs the voltage signal to 
the engine-ECU.

• Engine-ECU uses this voltage for DPF regenera-

tion control.

• The No. 2 exhaust gas temperature sensor (cata-

lyst temperature) is a kind of resistor, which has 
characteristics to reduce its resistance as the cat-
alyst temperature rises. Therefore, the sensor 
output voltage varies with the catalyst tempera-
ture, and becomes lower as the catalyst tempera-
ture rises.

TROUBLE JUDGMENT

Check Conditions

• Battery positive voltage is 8 − 16 V.

• 2 seconds later after the ignition switch has been 

in "ON" position or the engine has started up.

• Vehicle speed is 20 km/h or higher.

Judgment Criterion

• The No. 2 exhaust gas temperature sensor (cata-

lyst temperature) output voltage is 4.95 V or 
more.

AKB00271

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1 2

AB

BR-G

O-B

R-B

GR-R

Engine-ECU

No. 2 exhaust gas
temperature sensor
(catalyst temperature)

A-159

MU802601

No. 2 Exhaust Gas Temperature Sensor (catalyst temperature) Circuit

2

83

1

2

8

59

A-28

5 V

C-105

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

TROUBLESHOOTING

DIESEL FUEL

13A-234

PROBABLE CAUSES

• Failed No. 2 exhaust gas temperature sensor 

(catalyst temperature)

• Open circuit or harness damage in No. 2 exhaust 

gas temperature sensor (catalyst temperature) 
circuit or loose connector contact

• Failed engine-ECU

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13A-542

a. Item 118: No. 2 exhaust gas temperature sensor 

(catalyst temperature)

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Use Troubleshooting/

Inspection Service Points 

− How to Cope 

with Intermittent Malfunctions ).

NO : 

Go to Step 2 .

STEP 2. Connector check: A-159 No. 2 exhaust 
gas temperature sensor (catalyst temperature) 
connector

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Repair or replace the connector.

STEP 3. Check No. 2 exhaust gas temperature 
sensor (catalyst temperature) itself.

• Check No. 2 exhaust gas temperature sensor 

(catalyst temperature) itself (Refer to GROUP 17 
− Emission Control − Diesel Particulate Filter 
(DPF) System 

− No. 2 Exhaust Gas Temperature 

Sensor (catalyst temperature) Check ).

Q: Is the check result normal?

YES : 

Go to Step 4 .

NO : 

Replace the No. 2 exhaust gas temperature 
sensor (catalyst temperature). After 
replacing the No. 2 exhaust gas 
temperature sensor (catalyst temperature), 
carry out the forcible DPF regeneration. 
(Refer to GROUP 17 

− Emission Control − 

Diesel Particulate Filter (DPF) System 

− 

Forcible DPF Regeneration ).

STEP 4. Perform voltage measurement at A-159 
No. 2 exhaust gas temperature sensor (catalyst 
temperature) connector.

• Disconnect connector, and measure at harness 

side.

• Ignition switch: ON

• Voltage between terminal No. 1 and earth.

OK: 4.5 

− 4.9 V

Q: Is the check result normal?

YES : 

Go to Step 8 .

NO : 

Go to Step 5 .

1

2

AKB00272

A-159 (B)

Harness side
connector

Connector: A-159

No. 2 exhaust gas
temperature sensor
(catalyst temperature)

AB

1

2

AKB00272

A-159 (B)

Harness side
connector

Connector: A-159

No. 2 exhaust gas
temperature sensor
(catalyst temperature)

AB

TROUBLESHOOTING

DIESEL FUEL

13A-235

STEP 5. Connector check: C-105 engine-ECU 
connector.

Q: Is the check result normal?

YES : 

Go to Step 6 .

NO : 

Repair or replace the connector.

STEP 6. Check harness between A-159 (terminal 
No. 1) No. 2 exhaust gas temperature sensor 
(catalyst temperature) connector and C-105 
(terminal No. 59) engine-ECU connector.

NOTE: Before checking harness, check intemediate 
connector A-28, and repair if necessary.

• Check output line for open circuit.

Q: Is the check result normal?

AKA00089

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C-105 (B)

C-105 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-105

AB

1

2

AKB00272

A-159 (B)

Harness side
connector

Connector: A-159

No. 2 exhaust gas
temperature sensor
(catalyst temperature)

AB

AKA00089

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C-105 (B)

C-105 (B)

<R.H. drive vehicles>

Harness side connector

<L.H. drive vehicles>

Connector: C-105

AB