Evinrude E-tec 75 HP, Service Manual

Page: 163 / 344

163
FUEL SYSTEM
DIRECT INJECTION ELECTRICAL CIRCUITS
7
DIRECT INJECTION
ELECTRICAL CIRCUITS
The outboard’s 55 V alternator circuit supplies the
injectors and fuel circulation pump with the current
required to activate the fuel injectors and pump.
Unique circuits from the
EMM
distribute this cur-
rent to the specific injector or pump.
The
EMM
controls injector and pump operation by
rapidly connecting and disconnecting one side of
each component’s internal coil to ground. Current
must flow from the
EMM
to the injectors and
pump, through the winding of the component,
back to the
EMM
, and through the
EMM
to
ground. The injector’s internal coil provides
approximately 3 ohms of resistance in the injector
circuit.
Requirements for injector or circulation pump acti-
vation:
•
55 V output from the alternator to the
EMM
and
through the individual circuits; and
•
Switched ground connection provided by the
EMM.
IMPORTANT:
The 55 V alternator output is pro-
duced by stator input to
EMM
and rectifier circuits
of
EMM
.
Injector / Circulation Pump Circuits Diagram
1
2
3
5
6
7
8
12
13
14
15
16
9
10
11
7
6
5
4
3
2
1
13
12
11
10
9
8
26
24
25
23
22
21
20
19
17
16
15
14
18
J1-B
J2
4
1 2 3 4 5 6
2 3 4 5 6 1
2 3 1
2 3 1
2 3 1
2
1
002174
J1-A
6
7
8
10
11
9
5
1
2
3
4
3 3
1.
2.
3.
4. Stator
EMM
Fuel injector
Fuel circulation pump
5.
6.
7.
8. Capacitor
WHITE/RED (55 V)
BLACK ground wires
BLUE 9.
10.
11.
PURPLE
GREEN (2)
BROWN