Mitsubishi Eclipse. Manual - part 163

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-145

.

CIRCUIT OPERATION

• 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 voltage is 

out of specified range.

.

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)

• Not applicable

.

AK300060AB

C-54 (GR)

PCM

CONNECTOR: C-54 <A/T>

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-146

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• 2 seconds or more have passed since the staring 

sequence was completed.

Judgement Criteria

• Engine coolant temperature sensor output volt-

age has continued to be 0.1 volt or lower [corre-
sponding to a coolant temperature of 140

°C 

(284

°F) or higher] for 2 seconds.

.

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.

• Shorted engine coolant temperature sensor cir-

cuit, or connector 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

START

OUTPUT VOLTAGE > 4.6V

OUTPUT VOLTAGE < 0.1V

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

CONTINUOUS

FAILURE FOR 2secs

MONITORING

CONDITIONS?

NO

YES

AK301426

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-147

STEP 1. Using scan tool MB991958, check data list item 21: 
Engine Coolant Temperature Sensor.

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) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to the data reading mode for item 

21, Engine Coolant Temperature Sensor.

• The engine coolant temperature and temperature 

shown with the scan tool should approximately match.

(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.

STEP 2. Check connector B-11 at the engine coolant 
temperature sensor for damage.
Q: Is the connector in good condition?

YES : Go to Step 3.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 6.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

AK300404

1

2

CONNECTOR: B-11

AB

B-11 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-148

STEP 3. Check for short circuit to ground between engine 
coolant temperature sensor connector B-11 and ECM 
connector C-60 <M/T> or PCM connector C-54 <A/T>.
Q: Is the harness wire in good condition?

YES : Go to Step 4.
NO :  Repair it. Then go to Step 6.

AK300404

1

2

CONNECTOR: B-11

AB

B-11 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

AK300415

82

78

8180

89

90

91

92

79

87

71

74 73 72

76 75

77

85

88

83

84

86

CONNECTOR: C-60 <M/T>

AB

C-60 (G)

HARNESS CONNECTOR:
COMPONENT SIDE

AK300412

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

C-54 (GR)

CONNECTOR: C-54 <A/T>

AB

HARNESS CONNECTOR:
COMPONENT SIDE