Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual — part 232

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-127

DTC P0135: O

2

Sensor Heater Circuit Malfunction (bank 1 sensor 1)

AK000691

3 4

1 2

3 4

1 2

RED

-

WHITE

RED

-

WHITE

RED

-

WHITE

RED

BL

UE-

WHITE

BATTERY

A-21X

3

4

1

2

RIGHT BANK HEATED
OXYGEN SENSOR(FRONT)

B-27
MU802605

1

2

3

4

TO ECM
OR PCM

TO ECM
OR PCM

ENGINE CONTROL
MODULE(ECM)<M/T>
OR
POWERTRAIN CONTROL
MODULE(PCM)<A/T>

4

MFI
RELAY

C-51<M/T>,C-52<A/T>
(MU803784)

2

3 4

5 6

7 8

9

11 12 13 14 15 16 17 18 19 20

30

21 22 23

24 25

26 27 28 29

3132 33

34 35

1

10

ACX02481

CONNECTOR : B-27

RIGHT BANK
HEATED OXYGEN
SENSOR(FRONT)

AC

AK000226

AK000226AB

CONNECTOR : A-21X

MFI RELAY

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-128

CIRCUIT OPERATION

•

Power is supplied from the MFI relay (terminal 1)
to the right bank heated oxygen sensor (front)
heater.

•

The ECM (terminal 4) <M/T> or PCM (terminal 4)
<A/T> controls continuity to the right bank heated
oxygen sensor (front) heater by turning the power
transistor in the ECM <M/T> or PCM <A/T> "ON"
and "OFF."

TECHNICAL DESCRIPTION

•

The ECM <M/T> or PCM <A/T> checks whether
the heater current is within a specified range
when the heater is energized.

DTC SET CONDITIONS

Check Conditions

•

Engine coolant temperature is higher than 20

°

C

(68

°

F).

•

While the right bank heated oxygen sensor (front)
heater is on.

•

Battery positive voltage is at between 11 and 16
volts.

Judgment Criteria

•

Heater current of the right bank heated oxygen
sensor (front) heater has continued to be lower
than 0.2 ampere or higher than 3.5 ampere for 6
seconds.

•

One monitor during one drive cycle

TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are:)

•

Open or shorted right bank heated oxygen
sensor (front) heater circuit.

•

Open circuit in right bank heated oxygen sensor
(front) heater.

•

ECM failed. <M/T>

•

PCM failed. <A/T>

DIAGNOSIS

Required Special Tools
MD998464: Test Harness

STEP 1. Check connector B-27at the right bank heated
oxygen sensor (front) for damage.
Q: Is the connector in good condition?

YES : Go to Step 2.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 12.

AK000225

CONNECTOR : C-51<M/T>, C-52<A/T>

C-52

C-51

PCM<A/T>

ECM<M/T>

AJ

AK000208 AB

CONNECTOR : B-27

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-129

STEP 2. Check the right bank heated oxygen sensor
(front).
(1) Disconnect right bank heated oxygen sensor (front)

connector B-27 and connect test harness special tool,
MD998464, to the connector on the right bank heated
oxygen (front) sensor side.

(2) Measure the resistance between heated oxygen sensor

connector terminal 1 (red clip) and terminal 3 (blue clip).

Standard value: 4.5

−

8.0 ohm [at 20

°

C (68

°

F)]

Q: Is the resistance normal?

YES : Go to Step 3.
NO : Replace the right bank heated oxygen sensor (front).

Then go to Step 12.

STEP 3. Check the power supply voltage at right bank
heated oxygen sensor (front) harness side connector B-27.
(1) Disconnect the connector B-27 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 1 and ground.

•

Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES : Go to Step 5.
NO : Go to Step 4.

STEP 4. Check connector A-21X at the MFI relay for
damage.
Q: Is the connector in good condition?

YES : Repair harness wire between MFI relay connector A-

21X terminal 1 and right bank heated oxygen sensor
(front) connector B-27 terminal 1 because of open
circuit or short circuit to ground Then go to Step 12.

NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 12.

ACX02481

CONNECTOR : B-27

RIGHT BANK
HEATED OXYGEN
SENSOR(FRONT)

AC

AKX01624

HEATED
OXYGEN
SENSOR
EQUIPMENT
SIDE
CONNECTOR

MD998464

BLUE

RED

AC

AKX01498 AG

2

1

4

3

B-27 HARNESS
SIDE CONNECTOR

AK000226

AK000226AB

CONNECTOR : A-21X

MFI RELAY

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-130

STEP 5. Check the power supply voltage at ECM connector
C-51 <M/T> or PCM connector C-52 <A/T> by backprobing.
(1) Do not disconnect the connector C-51 <M/T> or C-52 <A/

T>.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 4 and ground by

backprobing.

•

Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage normal?

YES : Go to Step 8.
NO : Go to Step 6.

STEP 6. Check connector C-51 at ECM <M/T> or connector
C-52 at PCM <A/T> for damage.
Q: Is the connector in good condition?

YES : Go to Step 7.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 12.

AKX01534

1

2

3 4

5 6

7 8

9

10 11 12 13 14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

C-51<M/T>, C-52<A/T>
CONNECTOR HARNESS
SIDE VIEW

AF

AK000225

CONNECTOR : C-51<M/T>, C-52<A/T>

C-52

C-51

PCM<A/T>

ECM<M/T>

AJ