Mitsubishi Eclipse. Manual - part 578

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-855

STEP 12. Using scan tool MB991958, check actuator test 
item 11: Intake Manifold Tuning.

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 actuator test mode for item 

11, Intake manifold tuning solenoid.

• An operation sound should be heard and vibration 

should be felt when the intake manifold tuning solenoid 
is operated.

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

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

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-856

DTC P1603: Battery Backup Circuit Malfunction

AK103041

RED

-WHITE

RED

-WHITE

WHITE

WHITE

BATTERY

60 <M/T>
66 <A/T>

BATTERY
BACKUP

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

9 20A

8

RELAY
BOX

 C-55 <A/T>

(MU803781)

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

Battery Backup Circuit

65

43
50

42
49

41
48
60 61

64

46 47
58 59
67 68

45

56
66

52

51

44

53

62

54

63

57

55

C-58 <M/T>
(MU803782)

5

1

4

8

7

2

6

3

     C-07
MU801333

AK000312AJ

CONNECTOR:C-07

AK300244

CONNECTOR: C-55 <A/T>

AG

PCM

C-55 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-857

.

TECHNICAL DESCRIPTION

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

open circuit of battery backup line.

NOTE: When the system detects an open circuit in 
the battery backup line, it makes 1 failure judgment 
of other diagnostic trouble codes (DTCs).

.

DESCRIPTIONS OF MONITOR METHODS
Battery backup line voltage is under specified value.

.

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

.

AK300091

CONNECTOR: C-58 <M/T>

ECM

AC

C-58 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-858

DTC SET CONDITIONS

Logic Flow Chart

.

Check Conditions

• Starting sequence was completed.

• Battery positive voltage is higher than 10 volts.

Judgement Criteria

• Battery backup line voltage has continued to be 6 

volts or lower for 2 seconds.

.

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

• Open or shorted battery backup line, or connec-

tor damage.

• ECM failed. <M/T>

• PCM failed. <A/T>

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

START

MONITORING
CONDITIONS

CIRCUIT VOLTAGE

MALFUNCTION

CONTINUOUS

FAILURE FOR 2secs

NO

YES

YES

NO

< 6V

END

GOOD

NO

YES

AK301454