![background image](http://html.mh-extra.com/html/yanmar/3tnv88f/3tnv88f_service-manual_905559264.webp)
FAILURE DIAGNOSTIC LIST
14
-12
3T
NV88F
Service Manual
Failure Diagnostic List
Electric
system
Fuse meltdown, d
iscon
nection
In
spe
c
ti
on
an
d r
epla
c
e
m
ent
of
fu
se
Re
pair or re
placemen
t of
h
a
rness
For
h
a
rness
inspect
ion
met
hod,
.
Starter fault
Re
pair or re
placemen
t of
st
art
e
r
.
Alternator fault
Re
pair or re
placemen
t of
a
lte
rnat
or
.
Wiring discon
nection
Re
pair or re
placemen
t of
h
a
rness
d
isco
nnect
ion
Wiring short-ci
rcuit (insulat
or broken),
ele
c
tric power
load of adde
d device too
big
Inspe
c
ti
on
, repa
ir or repl
acement
o
f
ha
rn
es
se
s
Re
vi
ew of
adde
d
devices
Battery voltag
e descent
-
Inspe
c
ti
on
an
d cha
rgin
g o
f
bat
tery
.
Key switch fault, disconnection
Re
pair or re
placemen
t of
h
a
rness
K
e
y swit
ch r
eplaceme
n
t
For
h
a
rness
inspect
ion
met
hod,
.
Instantaneous interruption
of ke
y
sw
itc
h
K
e
y swit
ch r
eplaceme
n
t
Failu
re, disconnection,
short-circuit of
sta
rter rel
a
y
Re
pair or re
placemen
t of
h
a
rness
Re
placemen
t of
st
art
e
r rela
y
For
h
a
rness
inspect
ion
met
hod,
.
Main
relay fa
ult
(Error oth
er than contact sticking
that
ECU can’t detect)
Re
pair or re
placemen
t of
h
a
rness
Re
placemen
t of
ma
in relay
For
h
a
rness
inspect
ion
met
hod,
.
Actua
tor re
lay fault
(Error
of contact
that EC
U can’t det
ect)
Re
placemen
t
of
a
c
tuat
or
re
lay
The start assist rela
y may be faulty.
(Error
of contact
that EC
U can’t det
ect)
Re
placemen
t
of
st
art
a
s
sist
r
e
lay
Accelerator sen
s
or signal error
(Error at
which leve
l ECU
can’t detect)
Re
pair or re
placemen
t of
a
c
cele
rat
o
r
se
ns
or
Mo
nit
o
r the
a
c
cele
rat
o
r sensor by the
d
iagno
si
s t
ool.
Water tempe
rature sen
s
or signal error
(Error at
which leve
l ECU
can’t detect)
Re
placemen
t
of
wa
ter
t
e
mper
at
ure
sensor
Mo
nit
or t
he
co
oling
wat
er t
emp
erat
ure
by
the dia
gnosis to
ol.
Speed sensor signa
l error
(Cau
se of
noise etc. that ECU
can’t
detect)
Cl
eanin
g
o
r repla
c
e
m
ent
o
f sp
eed sensor
Re
pair or re
placemen
t of
f
uel
in
jectio
n
pu
m
p
Mo
nit
or
the
e
ngine
r
ota
tio
nal
speed
by
the dia
gnosis to
ol.
Rack p
ositio
n sen
s
or signal error
(Level that ECU can’t detect)
Re
pair or re
placemen
t of
f
uel
in
jectio
n
pu
m
p
Mo
nit
o
r t
he r
a
ck
posit
ion sen
s
o
r signa
l by
the dia
gnosis to
ol.
Op
eration defect of rack actuator
(Level that ECU can’t detect)
Re
pair or re
placemen
t of
f
uel
in
jectio
n
pu
m
p
Ch
eck t
he movemen
t of
rack
a
c
tuat
or
b
y
the dia
gnosis to
ol.
ECU failu
re lamp disconnected
Re
place th
e lamp.
Re
pair or re
place th
e harne
ss.
ECU faulty (ECU self diagno
sis fa
ilure)
Re
place th
e ECU.
Symptoms and condit
ions of failu
res
Cau
s
e
De
fecti
v
e sta
rt
Engine stall
after
sta
rt
Defective r
otation
cont
rol
Insufficient
engine output
Noise/vibra
tion
Lubricant
C
ooling
wa
ter
Inta
ke
Exhaust
F
uel
Electrics/electronics
Action
Referenced
page number
St
arte
r no
t
ro
ta
te
Starter
rotates
Exha
ust
fu
me
Speed change by accelerator n
ot available (constant sp
eed)
With
out lo
ad
At w
o
rk
Exhaust color
Knocking noise at combustion too high
Combus
tion noise uneven
Noise other than combustion from engine
Engine vibration too big
Lubricant consumption too much
Lubricant diluted with fuel
Lubricant mixed wit
h water
Oil pres
sure too low
(oil pressure lamp on)
Overheated (water temperature lamp on)
Water temperature too low
Pressure down (air cleaner lamp on)
Pressur
e up
At wo
rk
Blow-by too much
Exhaust temperatu
re up
Fuel consumption too much
Fuel mixed with water (oil-water separator
lamp on)
Fuel filter contaminated too e
arly
Battery charge defect (charge
lamp on)
ECU indicator lamp flashing
ECU indicator lamp not on just after key-on
(2 seconds)
Prescribed ECU control func
tion not operate
Fuse meltdow
n, disconnection (repe
ated)
ECU indicator lamp not on just after key-on
ECU indicator lamp on just
after key-on (2 seconds)
Engine not start (not even initial combustion)
Engine not start (stall after serial combustion)
Engine starts later then e
ver
None
Little
Much
Specified speed setting not available
Poor acceleration
Return to low speed not
smooth
Hunting
Hunting
Norm
al
White
Black
White exhaust color
Black exhaust color
3TNV
88F_
SVM_
A4.b
ook
12
ページ
2
01
2年
7月
26
日
木曜
日
午後
6時
4分