Mitsubishi L200. Manual - part 123

TROUBLESHOOTING

DIESEL FUEL

13A-288

OPERATION

• The electrical current source is supplied from the 

engine control relay (terminal No. 3) to the glow 
control unit (terminal No. 6). Also, it is supplied 
from the glow control unit (terminal No. 7) to the 
body earth.

• The request signal of operating the glow plug is 

input into the glow control unit (terminal No. 1) 
from the engine-ECU (terminal No.120).

• The voltage for the glow plug is applied from the 

battery to the glow control unit (terminal No.10).

• The voltage is applied from the glow control unit 

(terminal No.1, 2, 3 and 4) to each glow plug.

• The diagnosis signal is output from the glow con-

trol unit (terminal No. 9) to the engine-ECU (ter-
minal No.126).

FUNCTION

• The voltage applied to the glow control unit (ter-

minal No.10) from the battery is applied to each 
glow plug in the duty ratio according to the signal 
from the engine ECU.

TROUBLE JUDGMENT

Check Conditions

• While the engine is running

• The electrical continuity duty to the glow plug is 

17 

− 83 %.

Judgment Criterion

• When a failure of the glow control unit body is 

detected.

PROBABLE CAUSES

• Failed glow control unit

• Open/short circuit or harness damage in glow 

plug power supply circuit or loose connector con-
tact.

• Failed engine-ECU

DIAGNOSTIC PROCEDURE

STEP 1. Connector check: A-151 glow control 
unit connector

Q: Is the check result normal?

YES : 

Go to Step 2 .

NO : 

Repair or replace the connector.

STEP 2. Perform voltage measurement at A-151 
glow control unit connector.

• Disconnect connector, and measure at harness 

side.

• Voltage between terminal No.10 and earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 3 .

NO : 

Check and repair harness between A-151 

(terminal No.10) glow control unit connector 
and battery (fusible link 24).

• Check power supply line for open/

short circuit.

AKB00264

4 3 2 1
8 7 6 5

11 10 9

AB

A-151 (B)

Harness side
connector

Connector: A-151

AKB00264

4 3 2 1
8 7 6 5

11 10 9

AB

A-151 (B)

Harness side
connector

Connector: A-151

TROUBLESHOOTING

DIESEL FUEL

13A-289

STEP 3. Check harness between A-151 (terminal 
No. 10) glow control unit connector and battery 
(fusible link 24).

• Check power supply line for damage.

Q: Is the check result normal?

YES : 

Go to Step 4 .

NO : 

Repair the damaged harness wire.

STEP 4. M.U.T.-III diagnosis code.

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

YES : 

Go to Step 5 .

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use Troubleshooting/

Inspection Service points 

− How to Cope 

with intermittent Malfunctions ).

STEP 5. Replace the glow control unit.

• After replacing the glow control unit, reconfirm 

whether the diagnosis code is set.

Q: Is the diagnosis code set?

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

− Emission Control − 

Diesel Particulate Filter (DPF) System 

− 

Forcible DPF Regeneration ).

NO : 

Check is end.

Code No. P0652: Analog Sensor Reference Voltage No. 2 Too Low

FUNCTION

• The engine-ECU applies 5 V to the sensors other 

than the accelerator pedal position sensor (main)

• The engine-ECU checks whether the supply volt-

age is within the specified range.

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

Judgment Criterion

• The detected voltage of analog sensor reference 

voltage No. 2 is 4.86 V or less for 0.5 second. 
[Power supply for other than accelerator pedal 
position sensor (main)]

PROBABLE CAUSE

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

• After erasing the diagnosis code through M.U.T.-

III, ignition switch is "ON" position and confirm 
whether the diagnosis code is output.

Q: Is the diagnosis code set?

AKB00264

4 3 2 1
8 7 6 5

11 10 9

AB

A-151 (B)

Harness side
connector

Connector: A-151

TROUBLESHOOTING

DIESEL FUEL

13A-290

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 Malfunctions ).

Code No. P0653: Analog Sensor Reference Voltage No. 2 Too High

FUNCTION

• The engine-ECU applies 5 V to the sensors other 

than the accelerator pedal position sensor (main).

• The engine-ECU checks whether the supply volt-

age is within the specified range.

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

Judgment Criterion

• The detected voltage of analog sensor reference 

voltage No. 2 is 5.14 V or more for 0.5 second. 
[Power supply for other than accelerator pedal 
position sensor (main)]

PROBABLE CAUSE

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

• After erasing the diagnosis code through M.U.T.-

III, ignition switch is "ON" position and confirm 
whether the diagnosis code is output.

Q: Is the diagnosis code set?

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 Malfunctions ).

TROUBLESHOOTING

DIESEL FUEL

13A-291

Code No. P0683: Glow Control Unit Communication Abnormality <Euro5>

1

2

3
4

1

1

1

1

AKB00259

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

W

Glow System Circuit

Engine control relay

Glow control unit

A-20X

R

To engine-ECU

10

20A

Fusible link

Relay 
box

W-R

W-B

W-B

W-B

23

Fusible link 24

2

3

6

1

9

120

126

7

1

2

3

4

2

Y

Y

B

GR-R

LG-R

L

BR-Y

G

G-R

R

L-B

1

4

3

A-150

1

A-153

C-103

Engine-
ECU

No.1 
Glow plug

No.2
Glow plug

No.3
Glow plug

No.4
Glow plug

A-154

A-155

A-156

1

1

1

GND

10

OFF

ON

1

4

A-115

A-151

3

AB