Mitsubishi Eclipse. Manual — part 176

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-197

STEP 8. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 6 −

Other Monitor

P.13A-5

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0123 set?

YES : Retry the troubleshooting.
NO : The inspection is complete.

DTC P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control

AK000655

1 2

BL

ACK

YELL

OW

-GREEN

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

83 <M/T>
44 <A/T>

C-60 <M/T>
(MU803772)

C-54 <A/T>
(MU803781)

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

ENGINE COOLANT
TEMPERATURE SENSOR

B-11
(MU802406)

2

1

5V

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 6162 63

64 65 66

47

41

Engine Coolant Temperature Sensor Circuit

AK300052

ENGINE COOLANT
TEMPERATURE
SENSOR

CONNECTOR: B-11

AB

B-11 (B)

AK300060

ECM

CONNECTOR: C-60 <M/T>

AE

C-60 (G)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-198

.

CIRCUIT OPERATION

• A 5-volt voltage is applied to the engine coolant

temperature sensor output terminal (terminal No.
1) from the ECM (terminal No. 83) <M/T> or PCM
(terminal No. 44) <A/T> via the resistor in the
ECM <M/T> or PCM <A/T>. The ground terminal
(terminal No. 2) is grounded with ECM (terminal
No. 92) <M/T> or (terminal No. 57) <A/T>.

• The engine coolant temperature sensor is a neg-

ative temperature coefficient type of resistor. It
has the characteristic that when the engine cool-
ant temperature rises the resistor decreases.

• The engine coolant temperature sensor output

voltage increases when the resistor increases
and decreases when the resistor decreases.

.

TECHNICAL DESCRIPTION

• The engine coolant temperature sensor converts

the engine coolant temperature to a voltage and
output it.

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

this voltage is within a specified range.

.

DESCRIPTIONS OF MONITOR METHODS

• Engine coolant temperature sensor output volt-

age drops from over 40

°C (104°F) to under 40°C

(104

°F) and keeps under 40°C (104°F) for 5 min-

utes.

• Engine coolant temperature sensor output volt-

age does not reach close loop enable tempera-
ture within specified period when engine coolant
temperature sensor output voltage at engine start
is under 7

°C (45°F).

.

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)

• Not applicable

Sensor (The sensor below is determined to be

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

.

AK300060AB

C-54 (GR)

PCM

CONNECTOR: C-54 <A/T>

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-199

DTC SET CONDITIONS <Range/Performance problem-low input (time to reach closed loop
temperature) >

Logic Flow Chart

.

Check Conditions, Judgement Criteria

• About 60 − 300 seconds have passed for the

engine coolant temperature to rise to about 7

°C

(45

°F) after starting sequence was completed.

• However, time is not counted when fuel is shut

off.

.

START

END

YES

NO

NO

YES

MALFUNCTION

GOOD

TIME HAVE PASSED

AFTER STARTING?*

ENGINE
COOLANT
TEMP.

TEMP. WHERE
CLOSED LOOP
STARTS

>

MONITORING

CONDITIONS?

NO

YES

*: SEE DTC SET CONDITIONS-SET CONDITIONS, JUDGMENT CRITERIA

AK301432

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-200

DTC SET CONDITIONS <Range/Performance problem-drift>

Logic Flow Chart

.

Check Conditions, Judgement Criteria

• Engine coolant temperature decreases from

higher than 40

°C (104°F) to lower than 40°C

(104

°F).

• Then the engine coolant temperature has contin-

ued to be 40

°C (104°F) or lower for 5 minutes.

.

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: )

• Engine coolant temperature sensor failed.

• Harness damage in engine coolant temperature

sensor circuit, or connector damage.

• ECM failed. <M/T>

• PCM failed. <A/T>

START

END

NO

NO

YES

YES

MALFUNCTION

GOOD

UNDER 40˚C (107˚F)

300secs HAVE PASSED?

NO

YES

OVER 40˚C (107˚F)

YES

OVER 40˚C (107˚F)

NO

AK301435