Mitsubishi Colt Ralliart. Manual — part 54

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-170

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-131 alternator
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-131
alternator connector.

• Disconnect connector, and measure at harness

side.

• Ignition switch: ON

• Voltage between terminal No. 4 and earth.

OK: system voltage

Q: Is the check result normal?

YES :

Go to Step 6 .

NO :

Go to Step 3 .

STEP 3. Connector check: A-114 engine-ECU
connector or engine-CVT-ECU connector

Q: Is the check result normal?

YES :

Go to Step 4 .

NO :

Repair or replace the connector.

AK402015

2

1

3

4

AC

Connector: A-131

A-131 (G)

A-131 Harness side
connector

AK402015

2

1

3

4

AC

Connector: A-131

A-131 (G)

A-131 Harness side
connector

AK402745

6

4

2

5

3

1

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L

AD

A-114

Connector:

A-114

Harness side connector

Engine-ECU <M/T> or
engine-CVT-ECU <CVT>

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-171

STEP 4. Check harness between A-131 (terminal
No. 4) alternator connector and A-114 (terminal
No. 65) engine-ECU connector or
engine-CVT-ECU connector.

• Check output line for short circuit.

Q: Is the check result normal?

YES :

Go to Step 5 .

NO :

Repair the damaged harness wire.

STEP 5. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

YES :

Replace engine-ECU <M/T> or

engine-CVT-ECU <CVT>.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Use

Troubleshooting/Inspection Service Points

−

How to Cope with Intermittent Malfunctions

P.00-13

).

STEP 6. Perform voltage measurement at A-114
engine-ECU connector or engine-CVT-ECU
connector.

• Disconnect engine-ECU connector or

engine-CVT-ECU connector, and connect special
tool power plant ECU check harness
(MB991987), and then measure the voltage on
the check connector.

• Engine: Idle after warm-up

• Transmission: P range

• Radiator fan: Inactive

• Voltage between terminal No. 65 and earth.

OK: Switching the headlamps to ON from
OFF causes the voltage to fall.

Q: Is the check result normal?

YES :

Go to Step 9 .

NO :

Go to Step 7 .

AK402015

2

1

3

4

AC

Connector: A-131

A-131 (G)

A-131 Harness side
connector

AK402745

6

4

2

5

3

1

9

7

8

10

11

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66

L

AD

A-114

Connector:

A-114

Harness side connector

Engine-ECU <M/T> or
engine-CVT-ECU <CVT>

Battery

AK402745

6

4

2

5

3

1

9

7

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AE

A-114

Connector:

A-114

Engine-ECU <M/T> or
engine-CVT-ECU <CVT>

Battery

A-114 Special tool power plant ECU check
harness

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-172

STEP 7. Check harness between A-131 (terminal
No. 4) alternator connector and A-114 (terminal
No. 65) engine-ECU connector or
engine-CVT-ECU connector.

• Check output line for damage.

Q: Is the check result normal?

YES :

Go to Step 8 .

NO :

Repair the damaged harness wire.

STEP 8. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

YES :

Replace alternator.

NO :

Intermittent malfunction (Refer to Group 00

−

How to Use troubleshooting/Inspection
Service Points

− How to Cope with

Intermittent Malfunctions

P.00-13

).

STEP 9. M.U.T.-III diagnosis code

• Reconfirmation of diagnosis code.

Q: Is the diagnosis code set?

YES :

Replace engine-ECU <M/T> or

engine-CVT-ECU <CVT>.

NO :

Intermittent malfunction (Refer to Group 00

−

How to Use troubleshooting/Inspection
Service Points

− How to Cope with

Intermittent Malfunctions

P.00-13

).

AK402015

2

1

3

4

AC

Connector: A-131

A-131 (G)

A-131 Harness side
connector

AK402745

6

4

2

5

3

1

9

7

8

10

11

12

13

14

15

16

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66

L

AD

A-114

Connector:

A-114

Harness side connector

Engine-ECU <M/T> or
engine-CVT-ECU <CVT>

Battery

Main

Index

Group

TOC

TROUBLESHOOTING

MULTIPORT FUEL INJECTION (MPI) <4A9>

13A-173

Code No. P0638: Throttle Valve Control Servo Circuit Range/Performance Problem

OPERATION

• Refer to P2101 − Throttle valve control servo cir-

cuit

P.13A-198

.

FUNCTION

• Engine-ECU <M/T> or engine-CVT-ECU <CVT>

checks the electronic controlled throttle system
for abnormal conditions.

TROUBLE JUDGMENT

Check Conditions

• Ignition switch is in "ON" position.

• Battery positive voltage is more than 8.3 V.

• When variation in throttle valve opening angle is

small <M/T>

• Power is being supplied to the throttle valve con-

trol servo <CVT>

• Throttle position sensor (main) output voltage is

0.2

− 4.8 V.

Judgement Criteria (To targeted open degree, the

valve is stuck at the open side.)

• When the variation in throttle valve position is

small <CVT>.

or

• Throttle position sensor (main) output voltage has

continued to be above 0.5 V higher than the tar-
get throttle position sensor (main) voltage.

Check Conditions

• Ignition switch is in "ON" position.

• Throttle position sensor is normal.

Judgement Criterion

• Throttle position sensor (main) mid opening

learning value is 4.0 V or more.

PROBABLE CAUSES

• Failed throttle valve return spring.

• Failed throttle valve operation.

• Failed throttle valve control servo.

• Open/short circuit in throttle valve control servo

connector contact.

• Failed engine-ECU <M/T> or engine-CVT-ECU

<CVT>.

DIAGNOSIS

STEP 1. Check throttle body.

• Check whether the throttle valve return spring is

normal.

Q: Is the check result normal?

YES :

Go to Step 2 .

NO :

Replace the throttle body assembly.

STEP 2. Check the throttle valve control servo
itself.

• Check the throttle valve control servo control

motor itself (Refer to

P.13A-366

)

Q: Is the check result normal?

YES :

Go to Step 3 .

NO :

Replace electronic-controlled throttle valve.

Main

Index

Group

TOC