check engine DATSUN PICK-UP 1977 Service Manual

INSPECTION

Evaporator

Check

evaporator
for

leakage
or

damage
If

damaged
replace

Expansion
valve

Check

expansion
valve
for

leakage

or

clogging
If

clogged
clean
filter
in

expansion
valve
If

damaged

replace

RECEIVER
DRYER

AND

PIPING

REMOVAL
AND

INSTAUATION

Receiver
dryer

I
Disconnect

battery
ground
cable

2

Discharge
system
Refer
to

Dis

charging
System
under
General
Service

section

3

Disconnect

compressor
lead
wire

at

connector

4

Disconnect

cooling
pipes
at

joints

Acno

Fig
AC
39

Diaconnecting
coo

ing

pipes

Notes

a

Plug
all

piping

joints
immediately

after

pipe
disconnection
to

prevent

entry
of
dust
or
moisture
laden
air

into

receiver

dryer
or
air
aJOdi

tioning
system

b
Use

two
wrenches
when
dIsconnect

ing
cooling
pipes

5

Remove
four
screws

securing

receiver

dryer
bracket

to
vehicle

body

and
detach

compressor
relay
and

pres

sure
switch
as
an

assembly

6
To

install
receiver

dryer
and

piping
reverse
the
order
of
removal
Air

Conditioning

Notes

a

Apply
a
coat
of
fresh

compressor

oil
to

sealing
surfaces
when
con

necting
cooling

pipes

b
Use
two
wrenches
when

connecting

cooling
pipes

c

Evacuate

cooling
system
then
re

charge
with

refrigerant

Refer
to

Evacuating
and

Checking

System
under
General
Service

sec

tion

d
Check

refrigerant

leakage
if
neces

sary
repair

Refer
to

Evacuating
and

Charging

System
under

General
Service
See

tion

Condenser

Disconnect

battery

ground
cable

2

Discharge

system
Refer

to
Dis

charging
System
under
General

Service

section

3
Drain

engine
coolant

4

Remove
radiator

grille

5

Remove

radiator

shroud
and

radiator

On
automatic
transmission

models

disconnect
both

torque
converter
oil

hoses

Note

While

cooling
water
is
hot

take

precautions

against
scalding

6
Disconnect
two

pipes
from

con

denser
remove
two

screws

securing

condenser

Condenser

can
now
be

removed

AC485

Fig
AC

40

Removing
conden
er

Notes

a
Use

two
wrenches
when
disconnect

ing
pipe

joints

b

Plug
openings
immediately
after

disconnecting
pipes

7

To
install

reverse
the
order
of

removal

AC

29
Tightening
torque

Flare
nut
for

copper
tube

from

compressor

2
5
to
4
0

kg
m

i8
to
29
ft
Ib

Flare
nut

for

copper
tube

to
receiver

dryer

2
5

to
3
5

kg
m

i8
to
25
ft
lb

Notes

a
When

disconnecting
and

connecting

cooler

pipes
be
sure
to

use
two

wrenches

b

Apply
a
coat
of
fresh

compressor

oil
to

sealing
surfaces
when

con

necting
cooler

pipes

c

To

prevent

possibility
of

explosion

due
to

high

pressure
within

cooling

system
do

not
clean
condenser

with
steam

Always
use
cold
water

or

cold

compressed
air

d
Evacuate

cooling
system
then
re

charge
with

refrigerant

Refer
to

Evacuating
and

Charging

System
under
General

Service
sec

tion

e
Check

refrigerant
leakage
if
neces

sary
repair
Refer
to

Checking
for

Leaks
under
General
Service

sec

tion

INSPECTION

RecelYer

dryer

Check
for

refrigerant
leakage
or

damage

Check
for

proper
connection
of

two

lead
wires

running
to

pressure

switch

If

any
component

part
is
found

damaged
replace
receiver

dryer
and

pressure
switch
as

an

assembly

Condenser

I

Check

inlet
and
outlet

pipe
joints

and

sealing
surfaces
for

damage
Re

place
parts
if

damaged
or

leaky

2

Clogged
condenser
fins
or

air

pas

sages
may
reduce

cooling
efficiency
of

condenser
Clean
these

areas
with

dry

compressed
air

Piping

Check

piping
for

leakage
If

leakage

occurs
at
connections

retighten

connecting
nuts

Replace
if

leakage

persists

Inspection

Check

continuiry
in
fan
switch

circuit
with
a
test
lamp
or

an
ohm

meter

I

011
I
2
3

ICD

Tt

tt

AC772

Fig
AC
45
Fan
switch

RESISTOR
FOR
FAN
SWITCH

Removal
and
Installation

I

Disconnect
battery

ground
cable

2
Remove

glove
box

3
Remove

cooling
unit
Refer
to

Removal
and
Installation
under

Cooling
Unit

4

Disconnect
resistor
lead
wires
at

connector

@

O
sn
I
3n

CD
00
@

AC492

Fig
AC

46
Resistor

for
fan
switch
Air

Conditioning

5

Remove
resistor

assembly
from

upper
side
of

cooling
unit

Resistor
is

inserted
into

case

6
To
install

res
istor
for
fan
switch

reverse
the

order
of
removaL

Inspection

Test

continuity
between
resistor

and
fuse

THERMO
SWITCH

Removal
and
installation

1
Disconnect

battery

ground
cable

2

Remove

glove
box

3
Remove

duct
from

cooling
unit

4

Disconnect
thermo
switch
control

cable
and
lead
wires

5

Remove
thermo
switch

Note

Capillary
lube
is
fitted
into

groove
in
cooler
unit

6
To

install
thermo
switch
reverse

the

order
of
removal

I

I

AC773

Fig
AC
47

Removing
thermo
switch

AC

32
Inspection

I

Fully
move
thermo
swirch
lever

to
COLD

2

Test

continuity
between

ter

minals
with
a
test

tamp
or

an
ohm

meter

Continuity
should
exist

3

Dip
capillary
tube
end

into
ice

water
Test
continuity
between
ter

minals

Continuity
should
not
exist

4

Replace
if
switch
is

found
dam

aged

F
I
C
D
SOLENOID
VALVE

Removal
and
installation

I

Disconnect
battery
ground
cable

2
Disconnect
lead
wires
and
vacu

um

tube

3

Remove
two
screws
securing
sole

noid

valve
and
remove
solenoid
valve

AC77
4

Fig
AC

48
Removing
F
l
C
D

solenoid
valve

4
To
install
solenoid
valve
reverse

the
order
of
removal

Inspection

1
Test

continuity
in
solenoid
valve

circuit
with

a
test

lamp
or
an
ohm

meter

2
Turn
both
fan
switch
and
thermo

switch
on

3
Run

engine
at
idle
and
check
to

be
sure
that
vacuum
is

present
in
line

between
solenoid
valve
and

diaphragm