Mitsubishi Eclipse. Manual - part 196

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-277

DTC P0136: Heated Oxygen Sensor Circuit (sensor 2)

AK103266

BL

ACK

BL

UE

YELL

OW

FROM MFI RELAY

HEATED OXYGEN
SENSOR (REAR)

     C-23
MU801448

TO ECM
OR PCM

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

75 <M/T>
73 <A/T>*2

92 <M/T>
57 <A/T>*1

C-60 <M/T>
(MU803772)

C-54 <A/T>
(MU803781)

C-57 <A/T>
(MU803782)

NOTE
*1:PCM connector C-54 <A/T>
*2:PCM connector C-57 <A/T>

5

6

4

3

1

2

3 4 5 6

98

78

71

88 89

76 77

72
79

91

73
80

74

75

81

92

82 83
93

84 85

94

86 87

95 96

90

97

82

78

81

80

89 90 91 92

79

87

71

74

73

72

76

75

77

85

88

83 84

86

42 43
48 49 50 51 52 53 54 55 56 57

46

45

44

58 59

60 61 62 63

64 65 66

47

41

Heated Oxygen Sensor (rear) Circuit

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-278

.

CIRCUIT OPERATION

• A voltage corresponding to the oxygen concen-

tration in the exhaust gas is sent to the ECM (ter-
minal No. 75) <M/T> or PCM (terminal No. 73) 
<A/T> from the output terminal (terminal No. 3) of 
the heated oxygen sensor (rear).

• Terminal No. 4 of the heated oxygen sensor 

(rear) is grounded with ECM (terminal No. 92) 
<M/T> or PCM (terminal No. 57) <A/T>.

.

TECHNICAL DESCRIPTION

• The output signal of the heated oxygen sensor 

(front) is compensated by the output signal of the 
heated oxygen sensor (rear).

• The ECM <M/T> or PCM <A/T> checks for an 

open circuit in the heated oxygen sensor (rear) 
output line.

.

DESCRIPTIONS OF MONITOR METHODS
Heated oxygen sensor (rear) circuit is switched to 5 

volts intentionally when oxygen sensor output is 
low, and detects the malfunction if the output volt-
age changes to equal or greater than 4.5 volts. 
The above procedure is repeated when oxygen 
sensor is inactive.

.

MONITOR EXECUTION
Continuous

.

MONITOR EXECUTION CONDITIONS (Other 
monitor and Sensor)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• Heated oxygen sensor heater (front) monitor

• Heated oxygen sensor heater (rear) monitor

• Air/fuel ratio feedback monitor

Sensor (The sensor below is determined to be 

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

.

AK300054AB

C-23

HEATED OXYGEN
SENSOR (REAR)

CONNECTOR: C-23

AK300060

ECM

CONNECTOR: C-60 <M/T>

AE

C-60 (G)

AK300060

PCM

CONNECTORS: C-54, C-57 <A/T>

AI

C-57 (GR)

C-54 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-279

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 3 minutes or more have passed since the starting 

sequence was completed.

• Heated oxygen sensor (rear) signal voltage has 

continued to be 0.15 volt or lower.

• Engine coolant temperature is higher than 76°C 

(169

°F).

• Engine speed is higher than 1,200 r/min.

• Volumetric efficiency is higher than 25 percent.

• Monitoring time: 7 seconds.

START

V

F

 > =4.5V

2secs HAS PASSED

YES

YES

YES

NO

NO

NO

MALFUNCTION

MONITORING

CONDITIONS

YES

NO

MONITORING

CONDITIONS

+5V ON

AK301440

V

F

 < 0.15V

10secs HAS PASSED

YES

YES

NO

NO

END

MALFUNCTION

GOOD

MODULATE A/F CONDITION TO RICH

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-280

Judgment Criteria

• Input voltage supplied to the ECM <M/T> or PCM 

<A/T> interface circuit is higher than 4.5 volts 
when 5 volts is applied to the heated oxygen sen-
sor (rear) output line via a resistor.

.

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-ll Drive Cycle − 

Procedure 6 

− Other Monitor 

P.13A-5

.

.

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

• Heated oxygen sensor (rear) failed.

• Open circuit in heated oxygen sensor (rear) out-

put line, or harness damage.

• Open circuit in heated oxygen sensor (rear) 

ground line, or harness damage.

• ECM failed. <M/T>

• PCM failed. <A/T>

DIAGNOSIS

Required Special Tools:

• MB991958 (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

• MB991658: Test Harness 

STEP 1. Using scan tool MB991958, check data list item 59: 
Heated Oxygen Sensor (rear).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item 

59, Heated Oxygen Sensor (rear).

• Warming up the engine. When the engine is revved, the 

output voltage should repeat 0 volt and 0.6 to 1.0 volt 
alternately.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

NO :  Go to Step 2.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824