Mercury MerCruiser MCM 454 Mag MPI Service Manual page 637

GENERAL SYSTEM DIAGNOSTICS
MEFI 3 - J-2 Circuits (continued)
Circuit
(CKT)
Pin
Pin Num-
Func-
ber
tion
(#)
Master/
J2-21 916
Slave
Diag-
J2-22 451
nostic
Test
Discrete
J2-24 906
Switch
TP
J2-26 417
Signal
Map
J2-27 432
Signal
IAT
J2-30 472
Sensor
Ignition
J2-32 439
Fused
NOTE 1: Battery voltage for first two seconds, then 0 volts.
NOTE 2: Varies with temperature.
NOTE 3: Varies with manifold vacuum.
NOTE 4: Varies with throttle movement.
NOTE 5: Less than .5 volt (500 mV).
Index
Page 5E-44
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Normal Voltage
Wire Wire
Color
Ignition Engine
ON Running
YEL B+ B+
BLK/
B+ B+
WHT
TAN/
– –
WHT
DK .62V .62V
BLU
(NOTE 4) (NOTE 4)
LT 1.46V
4.9V
GRN
(NOTE 3)
TAN 5V
(NOTE 2)
PNK B+ B+
SERVICE MANUAL NUMBER 23
Diag-
nostic
Possible Possible
Trouble
Symptoms
Codes
DTC(s)
Lack Of Data From Other En-
None
gine (Dual Engine Only)
Incorrect Idle, Poor Perfor-
None
NONE
Poor Performance And Accel-
21
eration, Incorrect Idle
Poor Performance, Surge, Poor
33
Fuel Economy, Exhaust Odor
Poor Fuel Economy, Exhaust
23
None
90-861326--1 MARCH 1999
mance
Odor
No Start