Content .. 445 446 447 448 ..

Mitsubishi Eclipse. Manual - part 447

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-331

DTC P0150: Heated Oxygen Sensor Circuit (bank 2, sensor 1)

AK000694

1 2
3

ACK

WHITE

B-24
MU802605

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

LEFT BANK HEATED OXYGEN
SENSOR (FRONT)

FROM MFI RELAY

TO ECM
OR PCM

49 <M/T>*1
57 <A/T>*3

71 <M/T>*2
71 <A/T>*4

NOTE
*1:ECM connector C-58 <M/T>
*2:ECM connector C-62 <M/T>
*3:PCM connector C-55 <A/T>
*4:PCM connector C-59 <A/T>

88 89

76 77

72
79
91

73
80

81
92

82 83
93

84 85

86 87

95 96

100

76 77

72
79

C-62 <M/T>
(MU803783)

C-59 <A/T>
(MU803782)

43
50

42
49

41
48
60 61

46 47
58 59
67 68

56
66

C-58 <M/T>
(MU803782)

C-55 <A/T>
(MU803781)

42 43
48 49 50 51 52 53 54 55 56 57

58 59

60 61 62 63

64 65 66

Left Bank Heated Oxygen Sensor (front) Circuit

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-332

CIRCUIT OPERATION

• A voltage corresponding to the oxygen concen-

tration in the exhaust gas is sent to the ECM (ter-
minal No. 71) <M/T> or PCM (terminal No. 71)
<A/T> from the output terminal (terminal No. 4) of
the left bank heated oxygen sensor (front).

• Terminal No. 2 of the left bank heated oxygen

sensor (front) is grounded with ECM (terminal
No. 49) <M/T> or PCM (terminal No. 57) <A/T>.

TECHNICAL DESCRIPTION

• The left bank heated oxygen sensor (front)

detects the concentration of oxygen in the
exhaust gas; it converts that data to voltage, and
sends it to the ECM <M/T> or PCM <A/T>.

• When the left bank heated oxygen sensor (front)

begins to deteriorate, the heated oxygen sensor
signal response deteriorates also.

• The ECM <M/T> or PCM <A/T> varies the air/fuel

mixture to make it leaner and richer, and checks
the response speed of the left bank heated oxy-
gen sensor (front). In addition, the ECM <M/T> or
PCM <A/T> also checks for an open circuit in the
left bank heated oxygen sensor (front) output
line.

DESCRIPTIONS OF MONITOR METHODS
Left bank heated oxygen sensor (front) circuit is

switched to 5 volts intentionally when oxygen
sensor output is low, and detects the malfunction
if the output voltage 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

• Misfire monitor

• Fuel system monitor

Sensor (The sensor below is determined to be

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

AK300061

LEFT BANK
HEATED OXYGEN
SENSOR (FRONT)

CONNECTOR: B-24

B-24 (B)

AK300244

CONNECTORS: C-52, C-59 <A/T>

PCM

C-52 (GR)

C-59 (GR)

AK300091

CONNECTORS: C-58, C-62 <M/T>

ECM

C-58 (GR)

C-62 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-333

DTC SET CONDITIONS

Logic Flow Chart

Check Conditions

• 3 minutes or more have passed since the starting

sequence was completed.

• Left bank heated oxygen sensor (front) signal

voltage has continued to be 0.2 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

> =4.5V

2secs HAS PASSED

YES

MALFUNCTION

MONITORING

CONDITIONS

YES

MONITORING

CONDITIONS

+5V ON

AK301436

< 0.2V

10secs HAS PASSED

YES

END

MALFUNCTION

GOOD

MODULATE A/F CONDITION TO RICH

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-334

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 left bank heated
oxygen sensor (front) output line via a resistor.

OBD-ll DRIVE CYCLE PATTERN
Refer to , Diagnostic Function

− OBD-ll Drive Cycle −

Procedure 6

− Other Monitor.

P.13B-7

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

• Left bank heated oxygen sensor (front) deterio-

rated.

• Open or shorted circuit in left bank heated oxy-

gen sensor (front) output line, or harness dam-
age.

• Open circuit in left bank heated oxygen sensor

(front) ground line, or harness damage.

• ECM failed. <M/T>

• PCM failed. <A/T>

• Connector damage.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

• MD998464: Test Harness

STEP 1. Using scan tool MB991958, check data list item 11:
Heated Oxygen Sensor Bank 2, Sensor 1 (left front).

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

11, Heated Oxygen Sensor Bank 2, Sensor 1 (left front).

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

output voltage should be 0.6 to 1.0 volt.

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

output voltage should repeat 0.4 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

MB991911

16-PIN

MB991827

MB991824

Content .. 445 446 447 448 ..