battery DATSUN PICK-UP 1977 Repair Manual

HEATER
UNIT
ASSEMBLY

Removal

L
Disconnect

battery
ground
cable

2

Drain

engine
coolant

3

Remove
defroster
hoses

4

Remove
three

cable

retaining

clips
and
disconnect
control
cables

from
valves
and
water

cock

5

Disconnect
two

fan
motor
lead

wires
from
each
connector

6
Disconnect
two
resistor

lead
wires

from
each
connector

7

Disconnect
water
hoses
from
core

and
water
cock

8

Remove
three

heater
housing

mounting
bolts
and

dismount
heater

unit
from
vehicle

Installation

1

Position
heater
unit
under
instru

ment

panel
and
install
three
heater

unit

securing
bolts

2

Install
water
hoses

3
Position
heater

control
cables
to

room
valve
air
intake
valve
and
water

cock

4

Adjust
control
cable

length
for

proper
operation
as

outlined
in

Adjust

ment

5
Connect
fan
motor
wires
and

resistance
wires

to
each
connector

plug

6

Install
defroster
hoses

7

Connect

battery
ground
cable

8
Fill

cooling

systeIT

9
Run

engine
at
2
000

rpm
with

AIR

lever
in

the
HOT

position

Make
sure
that

engine
coolant
is
fIlled

up
to
correct
level

HEATER
CORE

Removal
and
installation

L

Drain

engine
coolant

2
Remove
defroster
hoses

3
Disconnect
water
hoses
from
inlet

and
outlet

pipes
of
heater
core

4

Remove
four

clips
and
front

cover
Body
Electrical

System

BE869A

Fig
BE
48

Removing
front
cov
r

S

Withdraw
heater
core
from
heater

housing

BE870A

Fig
BE
49

Removing
heater
core

6

Install
heater
core
in

the
reverse

sequence
of

removal

FAN
MOTOR

Removal
and
Installation

L
Dismount
heater
unit

assembly

from
vehicle

as
outlined
in
Removal
of

Heater
Unit
Assembly

2
Remove
nine

spring
clips
and

disassemble
heater

housing

3
Remove
fan
from
fan
motor

4
Remove
fan

motor

retaining

screws
and
fan
motor

S
Assemble
heater

housing
and
in

stall
heater
unit

to
vehicle
in
the

reverse

sequence
of
removal

as
out

lined
in

Installation
of

Heater
Unit

Assembly

I

CONTROL
ASSEMBLY

Removal
and
Installation

I
Remove
three
cable

retaining

clips
and
disconnect
control
cables

from
valves
and
cock

BE
29
2

Disconnect
three
lead
wires

from

each
connector

plug

3

Remove
radio
bezel
from
the

front
of
radio

following
instructions

in

steps
I

to
3
in

Removal
of
Radio

4

Remove
heater
control
knobs
and

heater

bezel

5

Remove
two

retaining
bolts
and

heater
control

assembly

6
Install
control

assembly
in
the

reverse

sequence
of

removal
When

connecting
control
cables

to
valves
and

cock

adjust
control
cable

length
as

outlined
in

Adjustment

ADJUSTMENT

AIR
lever

L
Move
AIR
lever
to
the
DEF

position

2

Open
air
intake

valve
and

connect

control

cable
to
air
intake
valve

3

Clip
control
cable
with
cable

re

taining
clip

Fig
BE
50
A
iT
intake
valve

4
Pull
room
valve

upward
and
con

nect
control
cable
to
room
valve

5

Clip
control
cable
with

cable
re

taining
clip

BE871A

Fig
BE
51

Room
valve

TEMP
lever

1

Move
TEMP
lever
to
the

OFF

position

2
Connect
control
cable
to
the
lever

of
water
ock
when

water
cock
lever
is

pulled
forward

fully
closed

3
Install
control
cable
on
water

cock
bracket
with
cable

retaining
clip

SPECIFICATIONS

Item

FAN
MOTOR

Rated

power
consumption

Revolution

rpm

Fan
dia
mm
in

TACHOMETER

The
tachometer
is

optional
on

model
HL620
It
is
an

integral
part
of

the

ignition
system
It
counts
the

pulses
entering
the

ignition
coil
and

indicates
the

number
of

engine
revolu

tions

REPLACEMENT

I

Remove

battery
ground
cable

2

Remve
cluster
lid

following

instructions
iri

steps
I
to
4
of
Removal

in

Combination
Meter
Body
Electrical

System

BE872A

Fig
BE

52
Water
cock

General
use
Extremely
cold

weather

use
2
RG
The
red

with

green

stripe
lead

wire

must
be

connected
to

flat

plate
terminal
at
back
of

combination
meter

3
B

The
black
lead

wire
must
be

connected

to
T

shaped
ter

minal
at
back
of

combination

meter

4

YR

The

yellow
with

red

stripe

lead
wire
must

be
connected

to

pole
terminal
at
back
of

combination
meter

6
Pass

tachllmeter
wires

through

grommet
on
hood
lock
control
wire

and
connect
to

negative
terminal
of

ignition
coil

Notes

a

Fix

grommet
with
an
adhesive

tape

or
a

sealing
compound
to

prevent

water

leakage

b
Attach
tachometer
wires
to
hood

lock

control
wire
with
an
adhesive

tape

BULB
REPLACEMENT

I
Remove
tachometer
as

previously

described

2

Twist
illumination
bulh
socket
at

back
of
tachometer
Bulb
with
socket

can
then
be

easily
removed

3

Remove
bulb

4

Install
new
bulb
in

reverse
se

quence
of
removal

Bulb

wattage

Tachometer
illumination

lamp
3
4W
12V

less
than
36W

3

600

110
433
12V

less
than
SSW

2

SOO

110
4
33

3
Disconnect

four
tachometer
lead

wire
connectors

They
are
connected

to

combination
meter
and
tachometer

cable

4

Remove
three

screws
and
then

remove
tachometer
from

cluster
lid

5

Install
in
reverse

sequence
of
re

moval
When

connecting
lead
wire

note

the

following

1
BW
The
black
with
white

striped

lead
wire

must
be
connected

to

identically
colored
ta

chometer

cable

coming
from

engine

compartment

BE

30
BE965

Fig
BE
53

Tachometer

SEAT
BELT

WARNING
SYSTEM

DESCRIPTION

Except
Canada

When

the

ignition
switch
is
turned

to
the
ON

position
the

warning

lamp
comes
on

and
remains
on
for
4

to
8

seconds
The

warning
buzzer

sounds
for
4

to
8
seconds
intermittent

ly
if
the
driver
s
seat
belt
is

not

fastened

properly

The
seat
belt

warning
system
con

sists
of
a
driver
s
belt
switch
a

warning

buzzer
a

warning
lamp
a
timer
unit

and
an

ignition
switch

For
Canada

When
the

ignition
switch
is
turned
Body
Electrical

System

to
the

ON

position
the

warning

lamp
comes
on
and
the

warning
buz

zer
sounds
if
the
driver

s
seat
belt
is

not

fastened

properly

The
seat
belt

warning
system
con

sists
of

a
driver
s

belt
switch

a

warning

buzzer

a

warning
lamp
and
an

igni

tion
switch

REMOVAL
AND

INSTALLATION

Ignition
switch

Refer
to

page
BE
22

for
Removal

and
Installation

Timer
unit

Timer
unit
is
fIXed

on
a
reinforce

ment
behind

glove
box

BE688B

I
Disconnect

battery
ground
cable

2
Remove

glove
box

3
Disconnect
timer
unit

connector

4
Remove
two
screws

retaining

timer
unit
on
reinforcement
Timer

unit
can
then
be
taken

out

S

Installation
is
in
the
reverse
se

quence
of
removal

Warning
buzzer

Warning
buzzer
is
fIxed

on
a
re

inforcement
behind

glove
box

Refer
to
the

preceding
timer
unit

for
Removal
and
Installation
BE282B

Fig
BE
54
Timer
unit

BE967A

Fig
BE
55
Warning
buzzer

Driver
s
seat
belt
switch

I
Remove
seat
belt

ecuring
bolt

2
Disconnect
belt
switch
lead
wire

at
connector

3

Seat
belt
can
then
be
taken
out

4

Installation
is
in
the

reverse
se

quence
ofremoval

BE
31
Warning
lamp
body

Warning

lamp
is

located
on
instru

ment

panel

I
Remove

cluster
lid

2
Disconnect

lead
wire

at
connee

tor

3
Remove

two
screws

retaining

lamp
body

4

Installation
is
in
the

reverse
se

quence
of
removal

WARNING
LAMP
BULB

REPLACEMENT

I
Remove
cluster

lid

2
Twist

warning
lamp
socket

Socket
with
bulb

can
then
be
taken

out

3

Pick

up
bulb

from
socket

4
Install
new
bulb
in
the
reverse

sequence
of
removal

Bulb

wattage

Seat
belt

warning
lamp
I
7W

INSPECTION

Warning
buzzer

Apply
12V

direct
current
between

CD
and

@
and
check
whether
buzzer

sounds
or
not

The
buzzer

must
sound
when

CD

and

@
are
connected
to

power

circuit
See

Figure
BE
55
for

warning

buzzer

Note
Make

sure
that

negative

terminal
of

power
circuit
is

always

connected

to

@
terminal

Timer
unit

Turn

ignition
key
to
the

ON

position
The

voltage
between

@
and

ground
must
be
12V
for
4

to
8

seconds
and
then

go
out
See

Figures

BE
54
and
BE
56

Belt
switch

Test

continuity
between
two
lead

wires
from
seat
belt
switch
with
ohm

meter
or
test

lamp

Body
Electrical

System

Circuit

diagram
of
seat
belt

warning
system

Non
California

modela

except
for
Canada

f
FUSIBLE
LINK

p

c

o

BATTERY

California
modela

f

Canada
modela

o

f
FUSIBLE
LINK

F
9

BATTERY

FUSIBLE
LINK

aP

c

BATTERY
IGNITION
SWITCH
FUSE

lOA

@

@I
TIMER

UNIT
I@

I

WARNING
fS

LAMP

l
2

IGNITION

RELAY

FUSE

1
lC
1
lOA

IGNITION
SWITCH

N

IGN
ITION
SWITCH
FUSE

lOA

BE
32
DRIVER
S

BELT
SWITCH

9

ORIVE
R
S

BELT
SWITCH

9

WARNING
r
i

LAMP

I
2
J

DRIVER
S

BELT

SWITCH

9

WARNING

fS

LAMP

I
2
J

Cf
BUZZER

BUZZER

BUZZER

BE689B

Fig
BE
56
Circuit

diagram
of
seat
belt

warning

system

Body
Electrical

System

TROUBLE
DIAGNOSES
AND
CORRECTIONS

HORN

Condition

Horn

does
not

operate

Horn

sounds

continuously

Reduced
volume

and
or
tone

quality
Probable
cause

Discharged
battery

Measure
specific
gravity
of

electrolyte

Burnt

fuse

Faulty
horn
button

contact

Horn
sounds
when

horn

relay
terminal
s

is

grounded

Inoperative
horn

relay

Horn

sounds
when
B
and

H
horn

relay

tenninals
are
connected
with
a
test
lead

Damaged
horn
or
loose
horn

terminal
con

nection

Short
circuited
horn

button
and
or
horn

button

lead
wire

When
light
green
lead
wire
is

disconnected

from
horn

relay
terminal
s

horn

stops
to

sound

Inoperative
horn

relay

Loose
or

poor
connector
contact

Fuse
relay
horn
and
or
horn

button

Damaged
horn

BE
33
Corrective
action

Recharge
or

replace
battery

Correct
cause
and

replace
fuse

Repair
horn
button

Replace
horn

relay

Correct
horn
te
inal
onnection
or

replace

horn

Repair
horn
button
or
its

wiring

Replace
horn

relay

Repair

Replace

CD
m
Cl
@
D
@

I

j

1
To
instrument
harness
IS
To
battery
30
To
check
connector

2
To
full
transistor
amplifier
16
To
fusible
link
3t
To
headlamp
L
U
type
2

California
models
only
17
To
engine
harness
No
2
32
To
sido
marker
lamp
L
B

3
To
hood
switch
18
To
alternator
33
To
front
combination
lamp
L
H

4
To
engine
compartment
lamp
1
9
To
front
combination
lamp
R
n
34
To
horn
Low

ll
l
S
To
washer
motor
20
To
headlamp
R
H
type
2
3S
To
horn
High

l
l
0
6
To
auto
choke
heater
relay
1
To
side
marker
lamp
R
n
36
To
B
C
D
D
cut
olenoid
California
models

7
To
detector
dri
e
counter
22
To
headlamp
R
B
type
1
only

Non
Califunia
model
except
for
Canada
23
To
ground
37
To
block
tcrminal
distributor
California

8
To
ignition
relay
California
models
only
i4
To
thermal
transmitter
models
only

9
To
floor
sensor
relay
California
modeb
only
is
To
distributor
Non
California
models
only
38
To
ignition
coil
Non
California
models
only

n
10
To
inhibitor
relay
A
T
only
26
To
8
C
D
D
cut
solenoid
Non
California
39
To
condenser

t
II
To
head
lamp
relay
models
only
40
To
ignition
coil
and
resistor
@

12
To
horn
relay
27
To
fuel
cut
solenoid
California
models
only

OJ
v

m
13
To
voltage
regulator
28
To
auto
choke
heater

g
e
14
To
cooler
cable
29
To
headlamp
L
R
type
1

OJ
to

o
Q
m
r0

C
1
i

Ql
CIl
Il
l
3

m
ii
bl
l

l
l
if
3
i
m
1
Kickdown
solenoid
AlT

2
Oip

3
Inhibitor
switch
AfT

4
Oip

5
Engine

6
Battery
cable

7
Engine
slinger

8
Battery
cable
r
0
w
I

I

cf
n

L
J

TO
ENGtNE
ROOM
HARNESS
OJ

o
Q
m

O
Q
CIl
II

D
3

Body
Electrical

System

EMISSION
WARNING
SYSTEM

California

models

CONTENTS

FLOOR
TEMPERATURE
WARNING

SYSTEM

California
models

DESCRIPTION

FLOOR

TEMPERATURE

WARNING
SYSTEM

California
models

DESCRIPTION

The
floor

temperature
warning

system
consists
of

a
floor

temperature

sensing
switch
installed
on

the
vehicle

floor
a

floor

temperature
relay
a

floor

temperature

warning
lamp
and

harnesses

When
the

floor

temperature
rises

to

an

abnormal
level

the

warning

lamp

will

come
on

to
call
the
attention

of

the

driver

i

f
FUSIBLE
LINK

P

BATTERY
IGNITION

SWITCH
BE
43

8E
43
WARNING
LAMP

TROUBLE

SHOOTING
GUIDE
BE
43

BE
44

The

warning

lamp
also
comes
on

during
operation
of

the

starter
motor

permitting
inspection
of

the

lamp
s

condition
The

lamp
goes
out
after
the

engine
starts

Refer

to
Section
EC
for

details

WARNING
LAMP

Bulb

replacement

I

Remove
cluster
lid

2

Twist

warni
ng

lamp
socket

Socket

with
bulb
can
then
be

taken

out

3
Pick

up
bulb
from
socket

IGNITION
RELAY

I
I
4

Installation
is
in
the

reverse
se

quence
of

removaL

Bulb

wattage

Floor

temperature

warning

lamp

17W

Lamp
body
replacement

I
Remove

cluster
lld

2

Disconnect
lead
wire
at
connee

tor

3

Remove
two
screws

retaining

lamp
body

4
Installation
is

in
the

reverse
se

quence
of

removal

FLOOR

I
l

I
SENSOR

RELAY

WARNING
I

LAMP
FLOOR
SENSOR

ON

FLOOR

TEMPERATURE

LOW

OFF
FLOOR

TEMPERATURE

HIGH

7

BE697B

Fig
BE
64
Circuit

diagram
of
floor

temperature
warning

system

BE
43

The

refrigerant
within
the

thermo

bulb

changes
in

pressure
through
the

super
heat

condition
of

vaporized
re

frigerant
gas
which
comes
out
of
the

evaporator
causing
the

deflection
of

the

diaphragm
The
lift

of
the

ball

valve
attached
to
the

diaphragm
is

changed
by
the
deflection
of
the
dia

phragm
thus

controlling
the
amount

of

refrigerant
passing
the

orifice

ELECTRICAL
CIRCUIT

DESCRIPTION

The

electrical
circuit

of
the
air

conditioner
consists
of
four
switches

two

relays
a
solenoid
valve
a
fan

motor
and
a

compressor
magnetic

clutch
Air

Conditioning

Diaphragm

Orifice

Valve
ball

AC729
4

Sensing
bulb

Fig
A
C
6

Expansion
value

The

following
wiring
diagram

pro

vides
a

complete
description
of
the

whole
circuit

When
the

ignition
switch
and
the

fan
switch
are
ON
the
main

relay
is

activated

causing
battery
power
to

flow

through
the
fan
motor
and
the

magnetic
clutch
The

magnetic
clutch

is

activated

by
the
thermo
switch

AC
5
000

l

1
Motor

2
Fan

3
Lower

case

4

Cooler
duct

5

Evaporator

6

Expansion
valve

7

Upper
case
8
Resistor

9

Main

relay

10
Thermo
switch

II
Cable

clamp

12

Cable

13
Harness

AC725

Fig
AC
7

Cooling
unit

pressure
switch
and

compressor
relay

The

blower
motor
fan

speed
is

con

trolled

by
the
fan
switch
and
resistor

The
solenoid
valve
is

also
activated

This
in
turn

causes
the

fast
idle
control

device
F
l

C
D
to
increase

engine

speed
when
the

vehicle
is

at
rest
with

the

engine
ON

MAIN
RELAY

The
main

relay
is
located
on
the

cooling
unit

When
the

ignition
switch
and
fan

switch

are
both
turned
on
the

COll

@

FAN
SWITCH

The

fan
switch

serving
as
a
control

unit
is

installed
on
the
center
console

This
switch

controls
the

blower
motor

speed
through
the
resistor
It
is
also

used
as
a

main

relay
switch

Fig
AC
I0
Fan
switch

THERMO

SWITCH

The
thermo

switch
is

located
on
the

upper
side
of
the

cooling
unit
and
is

controlled

by
the

cable
and
the
con

trollever
attached
to
the
console
box

It
is
so

designed
that
when
the
air

passing

through
the

evaporator
core
is

cooled
down

to
the

predetermined
Air

Conditioning

tacts
in
the

relay
are
closed
Then

electrical

power
from
the

battery
is

supplied
to
the
blower

motor
and
the

electrical
clutch
for
the

compressor

@

Dc

IDe

ID
1
1

l@

@
e

L
J

AC465

Fig
A
C
9
Main

relay

temperature
set

by
the

control
lever

it

automatically
turns

off
When
the

switch
is
turned
off
the

magnetic

clutch
is

turned
off

stopping
the
flow

of

refrigerant
inside
the

cooling
system

and

increasing
the

cooling
system
tem

perature

When
the

air
rises
to
the

pre

determined

temperature
the
thermo

switch

automatically
turns

on
In
this

way
the

temperature
of
the
air
dis

charged
from
the

cooling
unit
is
auto

matically
controlled
as
desired

PRESSURE

SWITCH

The

pressure
switch
is
turned
off

when

refrigerant
pressure
in
the

cooling
system
rises
to

an

abnormally

high
level
28

kg
cm2

398

psi
This

in

turn
turns
off
the

compressor

magnetic
clutch

actuating
the
com

pressor
relay
and

gradually
decreasing

pressure
in
the

cooling
system
When

the

pressure
drops
to
or
below
24

kg
cm2
341

psi
the

pressure
switch

again
turns
on

Thus

cooling

system
refrigerant

pressure
is

automatically
maintained
at

the

proper
value

a
t
all
times

AC
7
COMPRESSOR
RERAY

The

compressor
relay
is

attached
to

the
receiver

dryer
bracket
on
the

right

side

of
the

engine
compartment
This

relay
is

actuated
by
the

fan
switch

thermo
switch

and

pressure
switch
to

turn
on

and
off
the

compressor

magnetic
clutch

cv

1

2

AC731

Fig
A
C

11
Pressure
switch
and

compressor
relay

F
I
C
D
SOLENOID
VALVE

The
F
l
C
D
solenoid

valve
is
at

tached
to
the
dash

panel
in
the

engine

compartment
This
valve

supplies
vacu

um
to
the

F
I

C
D

diaphragm
through

the
vacuum
hose
connected

to
the

engine
intake
manifold
when
the

engine
is

at
idle
and

the

cooling
system

is
ON

thereby
raising
idle

speed
to
the

predetermined
rpm
800

IW

r

e

I

1
s

AC132

Fig
AC
12
F
l
C
D
solenoid

value