Yamaha F150B, Service Manual

Page: 113 / 458

4-8
Troubleshooting the power unit
0
1
2
3
4
5
6
7
8
9
10
A
2
7
W
a
te
r in fu
el
W
a
te
r in f
u
e
l
W/
F
A
ler
t
b
u
zz
e
r go
es out
wh
en
e
ngin
e
st
ar
ted
—
1.
Chec
k f
o
r w
a
te
r in f
uel f
ilt
er
.
—
2.
Mea
s
ure
t
he w
a
te
r det
e
c
ti
on
s
w
itch input
v
o
ltage
.
5-
23
A-3
3.
Chec
k th
e w
a
te
r de
te
ct
ion
s
w
itch f
o
r contin
uity
.
5-
23
4.
Chec
k f
o
r wir
ing
contin
uity
be
tw
een
t
h
e w
a
te
r det
ect
ion
s
w
it
ch and
eng
ine ECM.
5-
23
A-3
28
S
h
if
t p
o
s
itio
n
s
witc
h
malfunc
-
tio
n
Ir
re
gu
la
r s
ign
a
l
C
/E
——
1.
Chec
k th
e ge
ar
shif
t
o
p
e
ra-
ti
on.
10
-1
3
2.
Mea
s
ure
t
h
e neu
tr
al s
wit
ch
input v
o
ltage
.
5-
37
A-5
3.
Chec
k th
e ne
ut
ra
l s
w
it
ch f
o
r
cont
in
uit
y.
5-
37
4.
Chec
k f
o
r wir
ing
contin
uity
be
tw
een
t
h
e neu
tr
al s
wit
ch
an
d eng
ine
ECM.
5-
37
A-5
2
9
In
ta
k
e
pr
es
s s
e
n
-
s
o
r malfunction
Ou
t o
f specif
ica-
tio
n
C
/E
Higher idle
speed
Deg
ra
ded
a
c
ce
ler
a
tio
n
per
fo
rm
ance
Declining maxim
u
m engine s
p
eed
—
1.
Mea
s
ure
t
h
e
air
p
re
s
sur
e
sensor
inpu
t v
o
lt
ag
e
.
5-
32
A-5
2.
Mea
s
ure
t
h
e
air
p
re
s
sur
e
sensor
out
pu
t v
o
lt
a
g
e
.
5-
32
A-5
3.
Chec
k f
o
r wir
ing
contin
uity
be
tw
een
t
h
e
air
p
re
s
sur
e
sensor
and
e
n
g
ine ECM.
5-
32
A-5
3
7
In
ta
k
e
air
p
a
s
-
s
a
ge malfunction
Air leak
C
/E
Higher idle
speed
Ov
er
-r
e
v
o
lut
ion
at
f
u
lly o
pen
ed
t
h
ro
t-
tle
—
1.
Chec
k th
e O-
ri
ng
s an
d ga
s-
k
e
ts of
th
e int
a
k
e
sile
n
c
e
r
an
d int
a
k
e
ma
nif
o
ld
.
6-
16
6-
27
2.
Chec
k t
h
e
int
a
k
e
ma
nif
o
ld
f
o
r
cr
ac
ks
.
6-
27
3.
Chec
k th
e v
a
cuu
m
hose
.
6-
32
4
.
Sy
nc
hr
on
iz
e the
t
h
ro
tt
le
va
lv
e
s
.
6-
23
T
roub
le
code
Item
C
o
ndition
La
n ga
u
g
e
displa
y
Symp
to
m
R
e
m
ar
ks
Ch
ec
king
st
eps
Ref
e
r to
p
age