Mercury MerCruiser MCM 7.4L MPI User Manual

GENERAL SYSTEM DIAGNOSTICS
SERVICE MANUAL NUMBER 23
90-861326--1 MARCH 1999 Page 5E-29
MEFI 2 - 7.4L MPI Symptom Chart (J-1 Circuits) (Continued)
Pin
Circuit
(CKT)
Wire
Normal Voltage
Diagnostic
Tro ble
Possible
Pin
Pin
Function
(CKT)
Number
(#)
Wire
Color
Ignition
ON
Engine
Running
Tro
u
ble
Codes
DTC(s)
Possible
Symptoms
J2-12 Not Used – – – – – –
J2-13
IAC “A”
Low
442
LT
BLU/
BLK
Not Us-
able
Not
Usable
None
Rough Un-
stable or In-
correct Idle
J2-14
IAC “B”
Low
443
LT
GRN/
WHT
Not Us-
able
Not
Usable
None
Rough Un-
stable or In-
correct Idle
J2-15
Injector
Ground
450 BLK
0
(NOTE 5)
0
(NOTE 5)
None
Rough Run-
ning, Lack
Of Power,
Poor Perfor-
mance
J2-16 Not Used – – – – – –
J2-17 Not Used – – – – – –
J2-18 Not Used – – – – – –
J2-19 Not Used – – – – – –
J2-20
Fuel
Injector
Ground
450 BLK
0
(NOTE 5)
0
(NOTE 5)
None
Rough Run-
ning, Poor
Idle, Lack Of
Performance
J2-21
Injector
Driver
467
DK
BLU
B+ B+ None
Rough Idle,
Lack Of
Power, Stal-
ling
J2-22
Port Fuel
Jumper
901 BLK – – – –
J2-22
Port Fuel
Jumper
901 BLK – – – –
J2-23
Ignition
Control
Signal
423 WHT
0
(NOTE 5)
1.2V 42
Stall, Will
Restart In
Bypass
Mode, Lack
Of Power
J2-24
Ignition
Control
Bypass
424
TAN/
BLK
0
(NOTE 5)
4.5V 42
Lack Of
Power,
Fixed Timing
J2-25 Not Used – – – – – –
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Index

Mercury MerCruiser MCM 7.4L MPI Specifications

General

Brand	Mercury
Model	MerCruiser MCM 7.4L MPI
Category	Engine
Language	English