relay DATSUN PICK-UP 1977 Owner's Manual

Body
Electrical

System

WINDSHIELD
WIPER
AND
WASHER

Condition

Windshield

wiper

motor
does
not

operate

Wiper

operating
speed

is
too
slow

Wiper
speed
cannot

be

changed
correctly

Wiper
motor
continues

to

run
after
switch

is
turned
off
or

wiper

blades
do

not
return

to
correct

position
Probable
cause

Burnt
fuse

Damaged
motor

Check

wiper
motor
as
outlined
in

Inspec

tion

Loose
connection

Faulty
wiper
and

washer
switch

Test

continuity
through
switch
as

outlined

in

Inspection

Open

power
circuit

or

ground
circuit

Damaged
motor

Loose
or

poor
connection

Seized
or

rusted

wiper
linkage

Humming
occurs
on
motor
in

wiper
blade

operating
cycle

Wiper
blades
stick
on
windshield

glass

Raise
arm
and

operate
wiper
without

load

Faulty
wiper
switch

Damaged
motor

Faulty
auto

stop
operation

Poor
connection

Faulty
switch

BE
34
Corrective
action

Correct

cause
and

replace
fuse

Replace
wiper
motor

Repair

Replace

Repair

Replace
motor

Repair

Lubricate

or
replace

Clean
windshield

glass
and
or

replace
wiper

blade

Replace

Replace

Remove

auto

stop
device

cover
and

check

relay
contacts

Clean

dirty
contacts
or

repair
relay
plate

bending
if

necessary

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

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

Body
Electrical

System

TROUBLE
SHOOTING
GUIDE

Condition

Warning
lamp
does
not

light
in
START

posi

tion

of

ignition
switch
Probable
cause

Burnt
or

loose
bulb

Faulty
f1o
r

temperature
relay

Loose
connection

or

open
circuit

BE
44
Corrective
action

Replace
bulb

or
correct
bulb
socket

Conduct

continuity
test
and

repair
or
reo

place

Refer
to
Section

EC

Check

wiring
and
or

repair
if

necessary

OUTLINE
OF
AIR
CONDITIONER

REFRIGERATION

SYSTEM

CONDENSER

COMPRESSOR

RECEIVER
DRYER

COOLING
UNIT

ELECTRICAL
CIRCUIT

OUTLINE
OF
AIR

CONDITIONER

The

air
conditioner
consists

es

sentially
of
a

cooling
unit

compressor

condenser
receiver

dryer
and

piping

The

cooling
unit

secured
with

three

brackets
is
a

ttached
to
the

location

occupied
by
the

package

tray

in
the
dash

panel

The

cooled
air
from
the
duct

is

directed
into
the

passenger
compart
Air

Conditioning

DESCRIPTION

CONTENTS

AC
2

AC3

AC
3

AC3

AC4

AC4

AC
5
DESCRIPTION

MAIN

RELAY

FAN
SWITCH

THERMO

SWITCH

PRESSURE
SWITCH

COMPRESSOR
RELAY

F
I
C
D

SOLENOID
VALVE
AC
5

AC
7

AC
7

AC
7

AC
7

AC
7

AC
7

ment

through
the
three

outlets
at

the

instrument

panel

The

compressor
serves
to

compress

the

vaporized
refrigerant
and
is
attach

ed

through
the
bracket
to
the
loca

tion

occupied
by
the

mechanical
fuel

pump
on
the

engine

The
condenser
cools
the

compres

sed

refrigerant
vapor
sent

by
the
com

pressor
and
is

located
on

the
front
of
the
radiator
in

the

engine
compart

ment

The
receiver

dryer

serving
as
a

reservoir

for

storage
of
the

liquid
sent

by
the
condenser
is

located
on
the

right
in
the

engine
compartment

The

piping
consists
of

two
flexible

hoses

and
five

copper
tubes
which

connect
various

components
of
the

air

conditioning
system

I

Cooling
unit

2

Expansion
valve

3
Receiver

dryer

4

Comressor
5

Condenser

6
Duct

@
Flexible
hose

@
Copper
tube

AC
2
AC724

Fig
AC
1

Cooling
system

Air

Conditioning

RECEIVER
DRYER

The
receiver

dryer
serves
the

pur

pose
of

storing
the

liquid
refrigerant

The

amount
of
the

liquid
refrigerant

flowing
through
the

system
varies

with

the

operating
condition
of
the
air

conditioner
To
be
accurate
the

receiver

dryer
stores

excess
amount
of

refrigerant
when

the
heat
load
is

lowered
It

also
releases
stored

refriger

ant
when

additional

cooling
is
needed

thus

maintaining
the

optimum
flow
of

refrigerant
within
the

system

The
receiver

dryer
includes

a

strainer
and
desiccant

They
have
the

job
of

removing
moisture
and

foreign

particles
as
the

refrigerant
circulates

within
the

system

The

pressure
switch

is
installed

beside

sight
glass
of
receiver

dryer
The

purpose
of
the
switch

is
to

stop
the

compressor
operation
in
the
event

an

excessive

system

pressure
builds

up
on

the

high
pressure
lines
AC728

Fig
A
C
4

Compressor

To
e

ran
ion
alve

From
condenser

5

c
FJi

i

1

Z

i

3

c

o

I

COOLING
UNIT
o

L

o

W
7
R
o
3

J
J
r

t

AC230
I

Prc
surc
switch

2

Sight
glass

3
Strainer

4
De
kcant

Fig
AC
5
Receiver

dryer

The

liquid
refrigerant
evaporates
in

the

evaporator
with

the
aid
of
the

expansion
valve

Consequently
the
air

drawn

by
the
blower
motor
is

cooled

in

passing
through
the

evaporator

The

expansion
valve
restricts

the

liquid
refrigerant
as
it

passes
through
it

and

delivers

sprayed
refrigerant
to
the

evaporator
for

facilitating
refrigerant

evaporation
The

cooling
unit

includes
an

evapo

rator
and
an

expansion
valve
From

the
electrical

point
of
view

the

cooling
unit
consists
of
a

blower

motor

a
resistor
for
fan

speed
control

and
some
switches
and

relays

AC
4

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

1
I

6

I

BA

RY

i
Air

Conditioning

BW
c
J

BW

n
B

m

00
L
ELECTRIC

FUEL
PUMP

oB

tl

b@

L

t

FROM
LIGHT

SWITCH

c
J

LW
2
L

rRL
fZP
W

I
FUSE
15A

J
D
CJ
B

1
COMPRESSOR
RELAY
B

GL
I

lL

GL1J
ILLUMINATION

CONTROL

RHEOSTAT

3

ILLUMINATION

LAMP

I

I
MAIN
RELAY

FAN
SWITCH

I

r

1

UE
H

I

I
THERMO

SWITCH

COLOR

CODE

@

IC
PRESSU
1

rlTCH

D
D

G
c
J
oc

I
m

f
F
I
C
D

SOLENOID

COMPRESSOR

FUSE
LR

I

BW
O

W

ov
J

I

IG
0

0

OVJ

AC

6
B

BW

L

LW

LR

W

G

GL

RL
Black

Black
with
white

stripe

Blue

Blue
with

white

stripe

Blue
with
red

stripe

White

Green

Green
with

blue

stripe

Red
with
blue

stripe

IG

BW
t
1

n

L

IGNITION
SWITCH

AC727

Fig
A
C
B

Wiring
diagram
of
air
conditioner

system

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

Air

Conditioning

BLOWER
MOTOR
DIAGNOSES

Blower
motor

inoperative

Check
fuse

In
fuse
block

15A
W

Single
fuse
15A
at

cooling
unit

I

j

If
OK

Check
the

continuity
and

fitting
of
fan
switch

I

I

If
OK

I

I

Connect
fan
switch
to

wiring
harness

2

Turn
the

ignition
switch
ON
IG

3
Set
fan
switch
at
ON
1
2
or
3

position

Check
the

voltage
for
blower
motor

Blue
lead
wire
is

poweI
source

Blue
wire

with
white

stripe
is

for

grounding

I

I
Voltage

I

I

Check
the

continuity
and

fitting
of
resistance
on

cooling
unit

I

I
If
OK
If

damaged

I
I

Replace
blower
motor
Replace
resistance

AC

24
mown
fuse

Replace
fuse

j

If

damaged

I

I

Replace
fan
switch

No

voltage

Replace
main
relay