Mitsubishi Colt Ralliart. Manual - part 717

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-193

STEP 10. Check harness between A-101 (terminal 
No. 2) oil feeder control valve connector and 
A-114 (terminal No. 52) engine-ECU connector.

•

Check output line for damage.

Q: Is the check result normal?

YES : 

Go to Step 11.

NO : 

Repair.

STEP 11. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code output?

YES : 

Replace engine-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use Troubleshooting/Inspection 

Service Points 

− How to Cope with 

Intermittent Malfunctions 

P.00-13

).

AK402099

1

2

AC

Harness side 
connector

Connector: A-101

A-101(B)

AK402745

6

4

2

5

3

1

9

7

8

10

11

12

13

14

15

16

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18

19

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51

52

53

54

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56

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61

62

63

64

65

66

L

AF

A-114

Connector: 

A-114

Harness side connector

Engine-ECU

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-194

Code No. P1231: Trustful Check ASC <Vehicle with ASC>

FUNCTION

• Confirm abnormal signals of ASC through CAN 

communication.

TROUBLE JUDGMENT

Check Condition

• Ignition switch is "ON" position. 

Judgment Criterion

• The torque request signal from ASC-ECU is 

abnormal.

PROBABLE CAUSES

• Failed ASC-ECU

• Failed CAN

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Is diagnosis code related with CAN communication 

displayed?
YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13B-18

).

NO : 

Go to Step 2 .

STEP 2. M.U.T.-III other system diagnosis code

• Confirm whether the diagnosis codes are output 

from ASC-ECU.

Q:  Is the diagnosis code output?

YES : 

Perform the troubleshooting of ASC (Refer 

to Group 35C 

− Troubleshooting − 

Diagnosis Code Chart 

P.35C-6

).

NO : 

Replace engine-ECU.

Code No. P1233: Trustful Check Throttle Position Sensor (Main)

FUNCTION

• Compare the actual measurement of volumetric 

efficiency by an air flow sensor signal with volu-
metric efficiency estimated from a throttle position 
sensor (main) signal.

TROUBLE JUDGMENT

Check Conditions

• Ignition switch is in "ON" position.

• The air flow sensor is normal.

Judgment Criterion

• The difference between volumetric efficiency 

(actual measurement) by the air flow sensor and 
volumetric efficiency estimated from the throttle 
position sensor (main) exceeds the specified 
value.

PROBABLE CAUSES

• Failed throttle position sensor (main)

• Harness damage in throttle position sensor 

(main) circuit or loose connector contact

• Failed intake air system

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Is any other diagnosis code than P1233 output?

YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13B-18

).

NO : 

Go to Step 2 .

STEP 2. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item No. 79: Throttle position sensor (main)

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 

P.00-13

).

NO : 

Go to Step 3 .

STEP 3. Check air intake from intake hose and 
inlet manifold.

Q: Is the check result normal?

YES : 

Replace the engine-ECU.

NO : 

Repair.

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-195

Code No. P1234: Trustful Check Throttle Position Sensor (Sub)

FUNCTION

• Compare the actual measurement of volumetric 

efficiency by an air flow sensor signal with volu-
metric efficiency estimated from a throttle position 
sensor (sub) signal.

TROUBLE JUDGMENT

Check Conditions

• Ignition switch is in "ON" position.

• The air flow sensor is normal.

Judgment Criterion

• The difference between volumetric efficiency 

(actual measurement) by the air flow sensor and 
volumetric efficiency estimated from the throttle 
position sensor (sub) exceeds the specified 
value.

PROBABLE CAUSES

• Failed throttle position sensor (sub)

• Harness damage in throttle position sensor (sub) 

circuit or loose connector contact

• Failed intake air system

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Is any other diagnosis code than P1234 output?

YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13B-18

).

NO : 

Go to Step 2 .

STEP 2. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item No. 14: Throttle position sensor (sub)

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 

P.00-13

).

NO : 

Go to Step 3 .

STEP 3. Check air intake from intake hose and 
inlet manifold.

Q: Is the check result normal?

YES : 

Replace the engine-ECU.

NO : 

Repair.

Code No. P1235: Trustful Check Air Flow Sensor

FUNCTION

• Compare the actual measurement of volumetric 

efficiency by an air flow sensor signal with volu-
metric efficiency estimated from a throttle position 
sensor (main or sub) signal.

TROUBLE JUDGMENT

Check Conditions

• While engine is running.

• The throttle position sensor (main or sub) is nor-

mal.

• The air flow sensor is normal.

Judgment Criteria

• The difference between volumetric efficiency esti-

mated from the throttle position sensor (main) 
and volumetric efficiency estimated from the 
throttle position sensor (sub) exceeds the speci-
fied value.

• The difference between volumetric efficiency 

(actual measurement) by the air flow sensor and 
volumetric efficiency estimated from the throttle 
position sensor (main) exceeds the specified 
value.

• The difference between volumetric efficiency 

(actual measurement) by the air flow sensor and 
volumetric efficiency estimated from the throttle 
position sensor (sub) exceeds the specified 
value.

PROBABLE CAUSES

• Failed air flow sensor

• Damage in air flow sensor circuit or loose con-

nector contact

• Failed intake air system

• Failed engine-ECU

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4G1>

13B-196

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Is any other diagnosis code than P1235 output?

YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13B-18

).

NO : 

Go to Step 2 .

STEP 2. M.U.T.-III data list

• Refer to Data List Reference Table 

P.13B-335

.

a. Item No. 12: Air flow sensor

Q: Is the check result normal?

YES : 

Replace the engine-ECU.

NO : 

Check air flow sensor system (Refer to 
Code No. P0100 

P.13B-31

).

Code No. P1236: AD Converter

FUNCTION

• The input voltage from the accelerator pedal posi-

tion sensor (sub) is monitored whether which is 
converted normally into the digital signal within 
engine-ECU.

TROUBLE JUDGMENT

Check Condition

• Ignition switch is "ON" position.

Judgment Criterion

• When the input voltage from the accelerator 

pedal position sensor (sub) is periodically 0 V, the 
input voltage digital value shows more than 0.2 V.

PROBABLE CAUSE

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

• After clearing the diagnosis code through 

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

Q: Diagnosis code set?

YES : 

Replace engine-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Use 

Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunctions 

P.00-13

).

Code No. P1237: Trustful Check Accelerator Pedal Position Sensor

FUNCTION

• Compare accelerator pedal position sensor 

(main) output with accelerator pedal position sen-
sor (sub) one.

TROUBLE JUDGMENT

Check Conditions

• Ignition switch is "ON" position.

Judgment Criteria

• Difference is more than specified value between 

output voltage of accelerator pedal position sen-
sor (main) and output voltage multiplied by 2 of 
accelerator pedal position sensor (sub).

• When accelerator pedal position sensor (main) 

output voltage is constant, change amount of 
accelerator pedal position sensor (sub) output 
voltage is more than specified value.

PROBABLE CAUSES

• Failed accelerator pedal position sensor

• Damaged accelerator pedal position sensor cir-

cuit

• Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q: Diagnosis code set?

YES : 

Inspection chart for diagnosis code (Refer 

to 

P.13B-18

).

NO : 

Go to Step 2 .

Main

Index

Group

TOC