check engine DATSUN PICK-UP 1977 Service Manual

Engine
Electrical

System

DISTRIBUTOR
Non
California
models

CONTENTS

CONSTRUCTION

CHECKING
AND
ADJUSTMENT

CAP
AND
ROTOR

HEAD

CONTACT
POINT

CONOENSER
EE
30

EE
31

EE
31

EE
31

EE

31
ADVANCE
MECHANISMS

DISASSEMBL
Y

ASSEMBLY

SERVICE
DATA
AND
SPECIFICATIONS
EE
31

EE
32

EE
32

EE
33

CONSTRUCTION

The
distributor
consists
of
breaker

plate
with
contact

points

centrifugal

advance
mechanism
vacuum
control

ler
distributor
shaft
and

rotor

D

@

t

Cap
assembly

2
Rotor

head

assembly

3
Condenser

assembly

4

Ground
wire

assembly

5
Lead
wire
assem

bly

6
Contact

set

7

Breaker

plate
assembly

8

Packing

9
earn
assembly

10
Governor

spring

11
GoVernor

weight

12
Shaft

assembly

13
Vacuum
controller

14
Terminal

assembly

IS

Housing

16

Fixing

plate

17

O

ring

IS
Collar
v

i

@

D

@

EE32Q

Fig
EE
57

EE
30

CHECKING
AND

ADJUSTMENT

CAP
AND
ROTOR
HEAD

Cap
and
rotor
head
should
be
in

spected
periodically
as

specified
in
the

Maintenance
Schedule
Remove
cap

and
clean
all
dust
and
carbon
deposits

from

cap
and
rotor
If

cap
is
cracked

or
is

leaking
replace
with
a
De
one

CONTACT
POINT

Contact

point
should
be

replaced
in

accordance
with
the
Maintenance

Schedule

Standard

point
gap
is
0
45
to
0
55

mm
O
OIS
to
0

022
in
In

case
size

is
off
the
standard

adjustment
is
made

by
loosening
point
screws

Gap
gauge

is

required
for

adjustment

When

point
surface
is

rough
take

off

any
irregularities
with

fine
sand

paper
of
No
500
or
600
or
with
oil

stone

When
wear

on
contact

points
is

noticeable
replace
points
together

with
contact

arm
To

replace

proceed

as

follows

EE322

Fig
EE
58
Adju
ting
point

gap

EE321

I

Primary
lead
termina

2
Ground
lead
wire

3
Set
screw

4

Adjuster

5
Screw
Fig
EE
59
Breaker
Engine
Electrical

System

First
turn
out
set

screws
1
to

1
5

turns
at
contact
arm
and

primary
lead

wire

connection

just
for

enough
to

pull
out

primary
lead
terminal

Referring
to

Figure
EE

59
unSCrew

two
contact
set

fixing
screws

and

remove
lead
wire

While

holding
contact
arm

by

fingers

pull
out
contact
set

toward

you
by

raising
it

slightly
Contact

point
and

afm
can

then
be

removed

together

Install
new
contact

point
and

arm

assembly
in

reverse
sequence
of

removal

Coat
cam
with
a

light
coating

of

grease

ADVANCE
MECHANISMS

Specifications

Application

Vacuum
advance

Distributor

degrees
distributor

mmHg
inHg

Centrifugal
advance

Distributor

degrees

distribu
tor

rpm

For
Canada

Vacuum

advance
mechanism

mechanical

parts

If
vacuum
advance
mechanism
fails

to

operate
properly
check
for
the

following
items

and
correct
the
mal

function
as

required

1
Check
vacuum
inlet
for

signs
of

leakage
at
its

connection

Ifnecessacy

retighten
or

replace
with
a
new
one

2
Check
vacuum

diaphragm
for
air

leak

If
leak
is

found

replace
vacuum

controller

assembly

3

Inspect
breaker

plate
for
smooth

moving

If

pia
te
does
not

move

smoothly

this
condition
could
be
due
to

sticky

steel
balls
or

pivot
Apply
grease
to

steel
balls
or
if

necessary

replace

breaker

plate
as
an

assembly

EE
31
CONDENSER

Satisfactory
performance
of
con

denser

depends
on

capacity
and

degree

of
insulation

requiring
attention

to
be

sure

that
terminals
are
clean
and
set

screws
are

tight

Checking
of

condenser
is
made

by
a

condenser
tester

D4A4
06

D4A6
07
D4A4
07

D4A6
0S

Automatic

transmission
Manual
transmission

00
150
5

91

30
250
9

S4
00
170
6

69

6
50
300

1I
S1

00
550

11
0

2

300
00
600

110
1
950

Centrifugal
advance

mechanical

parts

When
cause
of

engine
malfunction

is

traced
to

centrifugal
advance
me

chanical

part
use
distributor
tester
to

check
its
characteristic

See
the

specifications
above

When

nothing
is

wrong
with
its

characteristic
conceivable
causes
are

break
down
abnormal

wearing
out
of

driving
part
or
others
So
do

not

disassemble

it

In

case
of

improper
characteristic

take
off
contact
breaker

assembly
and

check

closely
cam

assembly

governor

weight
shaft
and

governor
spring
etc

In
case

centrifugal
advance
me

chanical

part
is
reassembled
be

sure
to

check
advance
characteristic

by
dis

tributor
tester

DISASSEMBLY

To
disassemble
follow
the
below

proccd
ure

I
Take

off

cap
and
disconnect
rotor

head

2
Remove
vacuum
controller

EE291

Fig
EE
60
Removing
vacuum

controller

3
Remove
contact
set

Refer
to

Page
EE
31
when
contact

set
i
removed

EE323

Fig
EE
61

Removing
contact
tel

EE324

Fig
EE
62

Removing
breaker

plate
Engine
Electrical

System

4
When
breaker

plate
is
removed

be
careful
not
to
lose
steel

balls

between
breaker

spring
and
breaker

plate

5

Pul
roll

pin
out
and
siconnect

collar
to
remove
the
entire

rotating

parts

EE325

Fig
EE
63
Removing
roll

pin

EE326

Fig
EE

64
Removil1l
rotation
paTta

6
Remove

packing
from
the

top
of

cam

assembly
and
unscrew
earn
astern

bly
setscrew
Put
match
mark
across

earn
and
shaft
so
that
original
combi

nation
can
be
restored
at
assembly

EE
32
EE075

Fig
EE

65
Removing
cam

7

When

governor
weight
and

spring

are
disconnected
be
careful
not
to

stretch
or
deform

governor
spring

After

disassembling
apply
grease
to

governor
weights

ASSEMBLY

To
assemble
reverse
the
order

of

disassembly
Carefully
observe
the

fol

lowing
instructions

Align
match
marl

s
so
that

parts

are
assembled

to
their

original
posi

tions

2

Apply

grease
to
the

top
of
cam

assembly
as

required

3
Check
the

operation
of

governor

before

installing
distributor
on

engine

4

Adjust
ignition
timing
afteT
dis

tributor
is
installed
on

engine

Engine
Electrical

System

SERVICE
DATA
AND
SPECIFICATIONS

D4A4

06
D4A4
07

Type
D4A6
07
D4A6
08

Firing
order
1
3
4
2
13
4
2

Rotating
direction
Counterclockwise
Counterclockwise

Owen

angle
degree
490
to
550
490

to
550

Point

gap
mm
in
0

45
to
0

55
0
45
to
0
55

0
018
to

0
022
0
018
to
0

022

Point

pressure
kg
lb
0
40

to
0
55
0
40
to
0
55

0

88
to
1

21
0
88
to
1
21

Condenser

capacity
JlF
0
20

to
0
24
0
20

to
0
24

Condenser
isolate
resistance
Mrl
5
5

Cap
isolate
resistance
Mrl
50
50

Rotor
head
isolate
resistance
Mrl
50
50

Cap
carbon

point
length
mm
in
10

0
39
10
0
39

For
Canada

DISTRIBUTOR
California
models

CONSTRUCTION

CHECKING
AND
ADJUSTMENT

CAP
AND

ROTOR
HEAD

AIR

GAP

CONSTRUCTION

In
the
conventional
distributor
the

ignition
liming
is

detected

by
the
cam

and
breaker
arm
while
in
this
transis

tor

ignition
unit
it
is

detected

by
the

reluctor
on
the
shaft
and
the

pick
up

coil

provided
in

place
of
the
breaker

The

pick
up
coil
consists
of
a

magnet

coil
etc
The
amount
of

magnetic
flux

passing
through
the

pole
piece
in
the

coil
is

changed
at
the

moment
the

pole
CONTENTS

EE
33

EE
33

EE
33

EE
33
ADVANCE
MECHANISMS

DISASSEMBLY

ASSEMBLY

SERVICE
DATA
AND
SPECIFICATIONS
EE
33

EE
35

EE
35

EE
36

piece
faces
the

protrusion
of
the

re

luctor

and
then
the
electrical

signal
is

genera
ted
in
the

pick
up
coil

This
electric
signal
is

conducted

into

the
transistor

ignition
unit
which

in

turn
breaks
tI
e

primary
coil
current

running
through
the

ignition
coil
and

generates

high
voltage
in
the

secondary

winding
Also
this
transistor

ignition

EE
33
unit

utilizes
this
electric

signal
to

restore
the

primary
coil
to
the

original

state
after

cutting
off
the

primary

current
for
a
fIXed
time

The

centrifugal
and
vacuum
ad

vance
mechanisms

employ
the
con

ventional
mechanical

type
The
con

tactor
is
used
to
eliminate
vacuum

and

centrifugal
advance

hysteresis

I

t3
l

l

J
@

r
9

V

fW

@

@

CHECKING
AND

ADJUSTMENT

CAP
AND
ROTOR
HEAD

Cap
and

rotor
head
must
be
in

spected
periodically
as

specified
in
the

Maintenance
Schedule
Remove
cap

and
clean
all
dust
and
carbon

deposits

from

cap
and
rotor
from
time
to
time

If

cap
is
cracked
or
is

leaking
replace

with

a
new
one

AIR
GAP

Standard
air

gap
is
0
2
to

0
4
mm

0
008
to
0
016
in

If
the

gap
is

off
the
standard

adjustment
mould
be

made

by
loos

ening
pick
up
coil
screws

Gap
gauge
is

required
for

adjust

ment
Air

gaps
must
be

checked
from

time

to
time

Air

gap
0
2

to
0
4
mm

0
008
to
0

016
in
Engine
Electrical

System

tl

@

9

EE328

Fig
EE
67

Checking
oir

gap

To

remove

pick
up
cail
disconnect

distributor
harness

at
terminal
block

and
remove
screw

securing
pick
up
coil

ADVANCE
MECHANISMS

Specifications

Type

Item

Vacuum
advance

Distributor

degrees

Distributor

mmHg
inHg

Centrifugal
advance

Distributor

degrees

Distributor

cpm

EE34
1

Cap

assembly

2

Rotor
head

a55embly

3

Roll

pin

4

ReJuctor

S
Pick

up
coil

6
Contactoi

7
Breaker

plate

assembly

8

Packing

9
Rotor
shaft

10
Governor

spring

11
Governor

weigh
t

12
Shaft
a
Jscmbly

13

Cap
setter

14

Vacuum
controller

15

Housing

16

Fixing
plate

17
O

ring

18
Collar

EE327

Fig
EE
66

Exploded
view

of
di3tributor

assembly
and
distributor
harness
to

their

positions

EE329

Fig
EE

68

Remouing
pick

up
coil

D4F4
04
D4F4
Q3

Manual
Automatic

00

150
5
91

30

250
9
84

00

550

110
2

300
00

600

110
1
950

Vacuum

advance
mechanism

mechanical

parts

If
vacuum
advance
mechanism
fails

to

operate

properly
check
for
the

following
items

and
correct
the

prob

lem
as

required

1

Check
vacuum
inlet
for

signs
of

leakage
at
its
connection
If

necessary

retighten
or

replace
with

a
new
one

2

Check
vacuum

diaphragm
for
air

leak

If
leak
is

found

replace
vacuum

controller

assembly

3

Inspect
breaker

plate
for
smooth

moving

If

plate
does
not
move

smoothly

this

condition
could
be

due
to

sticky

steel

balls
or

pivot
Apply
grease
to

steel
balls
or
if

necessary
replace

distributor

assembly

Centrifugal
advance

mechanical

parts

When

cause
of

engine
malfunction

is
traced

to

centrifugal
advance
mecha

nical

parts
use
distributor
tester
to

check
its
characteristics
See
to
the

specifications
above

If

nothing
is

wrong
with
its

charac

teristics
conceivable
causes
are

faulty

or

abnormal
wear
of

driving
part
or

others
So
do
not
disassemble
it

In
the
event
of

improper
character

istics
check

closely
rotor

shaft
assem

bly

governor
weight
and
shaft

If

any
of
above

parts
are
malfunc

tioning
replace
distributor

assembly

DISASSEMBLY

To

disassemble
follow
the

pro

cedure
below

1
Take
off

cap
and
remove

rotor

head

2
Remove
two
screws
shown
in

Figure
EE
69
and
detach
vacuum

con

troller
Engine
Electrical

System

EE291

Fig
EE

69

Removing
vacuum

controller

3
Remove

pick
up
coil

assembly

4

Using
two

pry
bars

pry
reluctor

from
shaft
Be
careful
not

to
distort
or

damage
the
teeth
of
reluctor

Remove

roll

pin

S
Remove

breaker

plate
setscrews

and
remove

breaker

plate
assembly

E330

Fig
EE
70

Removing
breaker
plate

etscrews

6
Pull
roll

pin
out
and
remove

collar

7
Remove
rotor
shaft
and
drive

shaft
assembly

EE331

Fig
EE
71

Removing
rotor

shaft
and

drive

shaft
assembly

8
Mark
rotor
shaft
and

drive
shaft

Remove

packing
from
the

top
of

rotor

shaft
and
unscrew
rotor
shaft

setscrew

EE

35
EE075

Fig
EE
72

Removing
rotor

shaft

9

Mark
one
of
the

governor
springs

and
its
bracket
Also
mark

one
of
the

governor

weights
and
its

pivot
pins

10

Carefully
unhook
and
remove

governor

springs

11
Remove

governor
weights

Apply
grease
to

governor
weights

after

disassembling

ASSEMBLY

To

assem
ble

reverse
the
order
of

disassembly

Carefully
observe
the
fol

lowing
instructions

1

Align
match
marks
so
that

parts

are
assembled
to
their

original

posi

tions

2

If
for

any
reason
contactor
is

removed
from
breaker

plate
adjust

cam
to
contactor
clearance

to
0
3

mm

0
012
in

as
shown
in

Figure
EE
73

after
installation

T

EE298

Fig
EE
73
Cam
to
contactor

clearance

3

Ensure
that
reluctor
is

properly

orien

ted
when

installing
on
shaft

Always
drive
in

roll

pin
with
its

slit

toward
the
outer
end
of
shaft
See

Figure
EE

74
Be

sure
to
use
a

new
roll

pin

EE299

Fig
EE
74

Driving
in
roll

pin
Engine
Electrical

System

4

Apply
grease
to
the

top
of
rotor

shaft
as

required

5

Check
the

operation
of

governor

before

installing
distributor
on

engine

6

Adjust
ignition
timing
after

distri

butor
is
installed

on

engine

SERVICE

DATA
AND
SPECIFICATIONS

Type

Firing
order

Rotating
direction

Duty

Air

gap
mm
in

MU

Cap
insulation
resistance

Rotor
head

insulation
resistance
MU

Cap
carbon

point
length
mm
in
D4F4
03
D4F4
04

1
3
4

2

Counterclockwise

70
20
to
40
at

idling

0
2
to
0
4
O

OOS
to
0

016

More
than
50

More
than
50

10
0
39

TRANSISTOR

IGNITION
UNIT

California
models

DESCRIPTION

TRANSISTOR
IGNITION
UNIT

REMOVAL
AND

INSTALLATION

INSPECTION

1
POWER

SUPPLY
WI

RING
AND

BATTERY

CHECK

DESCRIPTION

TRANSISTOR

IGNITION

UNIT

The
transistor

ignition
unit

provides

the

following
functions

L
It

makes
and
breaks
the
electric

current
in

the

primacy
circuit

of
the

ignition
coil
2

CONTINUITY
CHECK

OF
PRIMARY

CIRCUIT

3

PICK
UP

COIL
CONTINUITY
CHECK

4
PICK
UP
COIL
POWER

SIGNAL

PULSE

CHECK

5
TRANSISTOR

IGNITION
UNIT
CHECK
CONTENTS

EE

36

EE

36

EE
37

EE
37

EE
37

2

The

duty
control

circuit
sets
the

rate
of
make

and
break
within

one

cycle
i
e

this

maintains

good

ignition

characteristics
of

engine
from
low

speed
to

high
speed
and
is

equal
to

the

dweU

angle
in

the

conventional

breaker

type
distributor

3

A

preventive
circuit

against
lock

EE
36
EE
36

EE
38

EE
38

EE
39

ing
is

provided
This

cuts
off
the

prilnaCY
electric
current
in

the

ignition

coil
when
the

ignition
switch
is

turned

on
with
the

engine
not

running

Each

component
part
of
this
unit

is

highly
reliable
however

should

any

part
be
found

faulty
the
entire
assem

bly
must
be

replaced

Engine
Electrical

System

Transistor

ignition
unit

r
1
Power

switching

circuit
Duty

control

circuit

To
starter

To
distributor

Ba

ttery
Ignition
coil
1
Spark
timing

1
Signal
mom

toring
circuit
Lock

j
preven
ling

circuit

nm

Distributor

EE437

Fig
EE
75
Transistor

ignition
unit
circuit

diagram

REMOVAL
AND

INSTALLATION

Transistor

ignition
unit
is

located

on
the

right
hand
dash

side

panel
in

passenger
compartment

Disconnect

battery
negative
cable

2
Disconnect

wiring
harness
from

unit

3
Remove
two

setscrews
and
te

move
unit

4

To
install
reverse
the
order
of

removal

Note
Be

sure
to
connect

wiring
har

nesses
to
their

proper

positio

Failure
to
do
so
will

damage
the

unit

Refer
to

Figure
EE
76

Fig
EE
76
External
view

of

ignition

unit
INSPECTION

If
the

engine
does

not
run
due

to

faulty
ignition
system
check
the

igni

tion

system
as
follows

Check
for
a
cracked
distributor

rotor
or

cap
and
corroded
tenninals

Visually

inspect
high
tension
wires

for

condition
and
if

necessary
use
an

ignition
oscilloscope
or
a
circuit
tester

to
make

performance
checks
Check

spark
plugs
and

adjust
gaps
as
neces

sary

Replace
a

spark
plug
which

is
not

suitable
for
further
use
If
the

above

checks
cannot
correct
the

problem

check
the
entire

ignition
system
with

an

oscilloscope
or

a
circuit

tester

L
CHECKING
WITH
AN

OSCILLOSCOPE

An

oscilloscope
can
be
used
for

checking
almost

all
the
items
in

a

transistor

ignition
system

CHECKING
WITH
A

CIRCUIT

TESTER

A
circuit
tester
can
not
be

used
for

the

duty
control
circuit

and

power

t18nsistor

performance
tests

Both

methods
use
of

an

oscilloscope
and
a

circuit
tester

are
described
in
this

section

EE

37
The
items

are
classified

by
numerals

in

accordance
with
the

objective
of

checks
to

be

performed
Several

wiring

diagrams
are
found

on

pages
EE
41

to

EE
45
The
thick
lines
indicate

the

objective
of

each
individual
item

check

When

checking
a
circuit
with
an

oscilloscope
or
a
circuit
tester
be

careful
not
to

confuse
the

polarity
of

the
lead
wires
if

potential
difference

exists
between
the
check

points
at

which
the
lead
wires
are
to
be
con

tacted

Also
do
not

attempt
to
con

nect
the

lead
wires
to

any
points
in
the

circuit
other

than
those

designated

Careless

handling
of
the
lead
wires

will

result
in

damage
to
the
transistor

ignition
unit

as
well
as
to
the
oscillo

scope
or
circuit

tester

The
connection
of

a
tachometer

or

a

timing
light
in

parallel
with
an

oscilloscope
or
a
circuit
tester
is
al

lowable

provided
that
such
a

connec

tion
is

made
with
due
consideration
to

wiring
connections

1
POWER
SUPPLY

WIRING

AND

BAnERY
CHECK

See

wIrIng
diagram

In

FIgure
EE
88

Procedure

I
Turn
on

ignition
switch

2

Connect

a
circuit
tester
or

an

oscilloscope
as
shown
in
the

figure

below

DC
50
volt

range

EE302

Fig
EE
77

Checking
power
supply

wiring
and

batt

ry

Criterion

When

power
source

battery

voltage
is

indicated
OK

Lower

or
no
indication
N
G

If
the
result

is
N
C
Take

the

following
measures

I
Check
BW
and
B
color

wire

harness

respectively
for

proper
con

ductance

2

Check

battery
terminals

for

proper
connection

3
Check

charge
condition
of
bat

tery
if
an

excessively
low

voltage
is

indicated

2

CONTINUITY
CHECK
OF

PRIMARY
CIRCUIT

2
1

CheckIng
prImary

circuit
See

wiring

diagram

In

Fig
EE
89

Proced
ure

I

Disconnect

L
color
wire

from

ignition
unit

2

Turn
on

ignition
switch

3

C
ooneet
a
cireui
t

tester
or
an

oscilloscope
as
shown
in

Figure
EE
78

DC

50
volt

range

tf
S

EE303

Fig
EE

78
Checking
primary
circuit

Criterion

When

Donnal

power
Source

battery

voltage
is

indicated

OK

Lower

or
no
indication

N

G

If
the

result
is

N
C

Take

the

following
measures

1

Check
BW

and
L
color

wire
Engine
Electrical

System

harness

respectively
for

proper
con

ductance

2

Check
resistor

and

ignition
coil

terminals
for
loose

contact

3

Check
resistor
and

ignition
coil

for

discontinuity

4
Check

WB

color
wire
harness

of

ignition
coil

assembly
for

proper

continuity

2
2

Chacklng
IgnitIon
coil

auembly
See

wiring

diagram
In

Fig
EE
90

Procedure

I

Disconnect

ignition
coil
and
dis

tributor

harness
from

ignition
coil

external
resistor

2

Connect
a
circuit
tester
as

shown

in

the

figure
below

Resistance

1

range

Q

o
fD

ro

EE336

Fig
EE
79

Checking
ignition
coil

assembly

Criterion

When

approximately
1
6

to

2

0

ohm
is

indicated

OK

More

than
2

0
ohm

N
C

If
the

result
is

N
C

Replace

ignition
coil

assembly

3
PICK

UP

COIL

CONTINUITY

CHECK

See

wirIng
dIagram
In

Figure
EE
91

Procedure

Disconnect
R

and
G

color

wires
from

ignition
unit

2
Connect

a
circuit

tester
as
shown

in
the

figure
below

EE

3B
Resistance

10

range

fp

EE305

Fig
EE

BO

Checking
pick
up
coil

Criterion

When

approximately
720
ohm

is

indicated

OK

Far
less
than
or
more

than

720
ohm
N
C

If

the
result
is
N
C

Replace

pick

up
coil

assembly

4

PICK
UP
COIL
POWER

SIGNAL

PULSE
CHECK

Procedure

I

Disconnect
anti

dieseling
solenoid

valve

connector

2

Connect
a
circuit

tester
as

shown

in

the

figure
below

3

Rotate
starter

motor

4

Read
the
tester
indication

AC
2
S
volt

range

EE306

Fig
EE
81

Checking
pick
up
coil

power

aignal
pulse

Criterion

When

pointer
deflects

slightly
OK

When

pointer
does
not
deflect

at
all

N
C

If
the

result
is

N
C

Replace

pick

up
coil

assembly

Procedure
with
an

oscilloscope

1
Disconnect
anti

dieseling
solenoid

valve
connector

2

Connect
a

positive
lead
of
an

oscilloscope
to
R
olor
wire

and
a

negative
lead
of
an

oscilloscope
to

G
color
wire

3
Set
a
SLOPE
select
switch
of

an
oscilloscope
to
the

positive
side
If

so

equipped

4

Rotate
starter
motor

5
Check
the

wave
form
as
shown
in

the

figure
below

EE268

Fig
EE
82
Wave

form
of
pick
up
coil

Criterion

When
the

wave
form
takes

the

shape
of
a

full
line
OK

When
the

wave
form
takes
the

shape
of

a
dashed
line

or
when

there

is
no
wave

form
N

G

If
the
result
is
N
G

Replace

pick
up
coil

assembly

5

TRANSISTOR
IGNITION

UNIT

CHECK
See

wiring

diagram
In

Figure
EE
92

Check
items
5
1
and
5
2
with

an

oscilloscope

Where

an

oscilloscope
is
not
availa

ble
check
to
make
sure
that
all

previ

ous
tests
are

satisfactory
and
that
no

spark
is

issuing
from
the

secondary

high
tension
wire

If

everything
else
is

satisfactory

then
the
transistor

ignition
unit
is

faulty
or
there
is

discontinuity
in
the

secondary

high
tension
wire

Replace

the

faulty
part
After

replacement

check
the

sparks
from
the

secondary

cord

5
1

Checking
operatIon

of
transIstor

Ignition
unit

Procedure

I

Connect

ignition
coil
and
dis

tributor
harness
to

ignition
coil
exter

nal
resistor
Engine
Electrical

System

Oscilloscope

o

EB

80

To

body
metal
Ignition
coil
terminal

8W

r
8

0

C
0

EB

Fig
EE
83

Checking
operation
of
transistor

ignition
unit
EE307

@

@

2

Connect

wiring
harness
to
the

ignition
unit

3
Disconnect
anti

dieseling
solenoid

valve
connector

4

Connect
oscilloscope
as
shown
in

Figure
EE
83

rotate
the
starter
motor

and
observe
the
wave

form
on
the

oscilloscope

Criterion

See

Figure
EE
84

When

a
wave
form
similar
to

a
is
observed
OK

When
a
wave
form
similar
to

b
is

obseIVed

or
when
no
wave
form
is

observed
N

G

If
the
result
is
N
G
the
fault
lies

either
in
the
transistor
unit

or
in
the

secondary
high
tension
wire

Replace
these

parts

EE
39
EE452

Fig
EE
84
W
uve

form
of
pulse

If
an

oscilloscope
is

not
avail

able

Procedure

1
Connect

ignition
coil
and
dis

tributor
harness
to

ignition
coil
exter

nal
resistor

2

Connect

wiring
harness
to

igni

tion
unit

3

Disconnect
anti

dieseling
solenoid

valve

connector

4

Keep
the

secondary
high
tension

wire
end
4
to
5

mm
0
16
to
0
20
in

away
from

engine
block
rotate
the

starter
motor
and
check

whether

sparks
fly
across
the
clearance

Criterion

Where
sparks
issue
OK

Where

no
spark
issues
N

G

If
the
result
is
N
G
the
fault

lies
either
in

the
transistor
unit
or
in

the

secondary
high
tension
wire

Replace
these

paris