1977 DATSUN PICK-UP check engine

Automatic
Transmission

TROUBLE

DIAGNOSIS
AND
ADJUSTMENT

INSPECTION
AND
ADJUSTMENT

BEFORE

TRQUBLE
DIAGNOSIS

TESTING

INSTRUMENT
FOR

INSPECTION

CHECKING
OIL

LEVEL

INSPECTION
AND
REPAIR
OF

OIL
EAKAGE

CHECKING

ENGINE
IDLING

REVOLUTION

CHECKING
AND
ADJUSTING

KICKDOWN

SWITCH
AND

DqWNSHIFT
SOLENOID

N
J
J
CII
Q

t
L
8li
p

JYSTMs
T
OF

MANUAL
LINKAGE

CHECKING
AND

ADJUSTING

INHIBITOR

SWITCH

STALL
TEST

STALL
TEST

PROCEDURES

JUDGEMENT

Since
most
automatic

transmission

troubles

can
be

repaired

by
simple

adjustment
do
not
disassemble
im

mediately

Firstly

inspect
and

adjust
the
auto

matic
transmission

in

place
utilizing

the
Trouble

Shooting
Chart

If
the
trouble
can

not
be
solved

by

this

procedure
remove
and
disas

semble

the
automatic
transmission

It

is

advisable
to
check

overhaul
and

repair
each

part
in
the

order
listed
in

the
Trouble

Shooting
Chart

I
In
the
Trouble

Shooting
Chart

the

diagnosis
items

are

arranged
ac

cording
to

difficulty
from

easy
to

difficult
therefore

please
follow
these

items
The
transmission
should
not

be

removed
unless

necessary

2
Tests
and

adjustments
should
be

made
on
the
basis
of
standard
values

and

the
data

should
be
recorded

INSPECTION

AND

ADJUSTMENT

BEFORE

TROUBLE
DIAGNOSIS

TESTING
INSTRUMENT
FOR

INSPECTION

I

Engine
tachometer

2
Vacuum

gauge
ROAD
TEST

VEHICLE
SPEED

AT
GEAR

SHIFT

CHECKING
SPEED
CHANGING

CONDITION

CHECKING
ITEMS
DURING
SPEED

CHANGE

SHIFT
SCHEDULE

LINE

PRESSURE
TEST

LINE

PRESSURE

governor
feed

pressure

JUDGEMENT
IN

MEASURING
LINE

PRESSURE

At
49

TR6
uBLE
SHOOTINC
CHART

INSPECTING
ITEMS

TROUBLE

SHOOTING
CHART
FOR

3N71B

AUTOMATIC
TRANSMISSION

TROUBLE

SHOOTING
GUIDE
FOR

3N71B

AUTOMATIC
TRANSMISSION
CONTENTS

AT
4B

AT
48

AT
4B

AT

49

AT
49

AT
49

AT
49

AT
50

AT

50

AT
50

3
Oil

pressure
gauge

It
is
convenient

to
install
these

instruments
in
a

way
that
allows
meas

urements
to
be
made
from
the
driver
s

seat

CHECKING
OIL
LEVEL

In

checking
the
automatic
transmis

sion

the
o
illevel
and
the
condition
of

oil
around
the
oil
level

gauge
should
be

examined
This
is

an

easy
and
effective

trouble

shooting

procedure
since

some

changes
in
oil
condition

are
often

linked
with

developed
troubles

For
instance

Lack
of
oil
causes

faulty
operation

by
making
the
clutches
and

brakes

slip
resulting
in

severe
wear

This
is
because
the
oil

pump
sucks

air

causing
oil

foaming
thus

rapidly

deteriorating
the
oil

quality
and

pro

ducing
sludge
and

varnish

Excessive
oil
is

also
bad
because
of

oil

foaming
caused

by
the

gears

stirring

up
the
oil

During
high
speed

driving

excessive

oil
in

the

transmission
often

blows
out

from
the
breather

Measuring
011
level

To
check
the
fluid
level
start
the

engine
and
run
it
until
normal

operat

T
AO
AT
51

AT
51

AT

52

AT
52

AT
52

AT

52

AT

53

AT
3

AT

53

AT

53

AT

54

AT
57

ing
temperatures
o

temperature
SO

to
800C

122
to
l760F

Approxi

mately
ten

minute
of

operation
will

raise
the

temperature
to
this

range

and

engine

idling
conditions

are
stabi

lized
Then

apply
the
brakes
and

move
the

transmission
shift
lever

through
all
drive

positions
and

place
it

in

park
P

position
In

this

inspec

tion
the
car
must
be

placed
on
a
level

surface

The
amount
of
the
oil
varies

with

the

temperature
As
a
rule
the
oil
level

must
be
measured
after
its

temper

ture
becomes

sufficiently
high

1

Fill
the
oil
to

the
line
H
The

difference
of

capacities
between
both

H
and
L
is

approximately
0
4

liter
Ji
V
S

p
Y

Imp
pl
and

therefore
do

not
to
fill

beyond
the

line

H

2
When

topping
up
and

changing

oil
care
should
be
taken
to

prevent

mixing
the
oil
with
dust
and
water

InspectIng
011

condition

The
condition
of

oil

sticking
to
the

level

gauge
indicates
whether
to
over

haul
and

repair
the
transmission

or

look
for
the

faulty

part

If
the
oil
has
deteriorated
to
a

varnish
ike

quality
it

causes
the

con

trol
valve
to
stick
Blackened
oil
indi

cates
a
burned
clutch
brake
band
etc

In

these
cases
the

transmission
must

be

repaired

Notes

a
In

checking
oil

level
use

special

paper
cloth
to
handle
the
level

gauge
and
be
careful
not
to
let
the

scraps
of

paper
and
cloth
stick
to

the

gauge

b
Insert
the

gauge
fully
and
take
it

out

quickly
before

splashing
oil

adheres
to
the

gauge
Then
observe

the
level

c
Use
automatic
transmission
fluid

having
DEXRON
identifications

only
in
the
3N71B
automatic
trans

mission

d

Pay
attention
because
the
oil
to
be

used
differs
from
that
used
in

the

Nissan
Full
Automatic
TranSJTIis

sion
3N71A
Never
mix
the
oils

INSPECTION
AND
REPAIR

OF
OIL
LEAKAGE

When
oil

leakage
takes

place
the

portion
near
the

leakage
is
covered

with
oil

presenting
difficulty
in

detecting
the

spot
Therefore
the

places
where
oil
seals
and

gaskets
are

equipped
are
enumerated
below

11
Converter

housing

Rubber

ring
of
oil

pump
housing

Oil
seal
of
oil

pump
housing

Oil
seal
of

engine
crankshaft

Bolts
of
converter

housing
to
case

2
Trarismission
and
rear
extension

Junction
of
transm
ss
ion

and
rear

extension
J

Oil
cooler
tube
connectors

Oil

pan

Oil

pressure
inspection
holes
Refer

to

Figure
AT
il2

Mounting
portion
of
vacuum
dia

phragm
and
downshift
solenoid

Breather
and
oil

charging
pipe

Speedometer
pinion
sleeve

Oil
se
l
of
rear
extension

To

exactly
locate
the

place
of
oil

leaka
le
proceed
as
follows

Place
the
vehicle
in

a

pit
and

by

sampling
the
leaked
oil
determine
if
it

is
the

torque
converter
oil
The

torque

converter
oil
has
a
color
like
r
d
wine

So
it
is

easily

distinguished
from

engine

oil
or

gear
oil
Automatic
rransmission

Wipe
off
the

leaking
oil
and
dust

and
deiecl
the

spol
of
oil

eakage

l
se

nonflammable

organic
solve
t
s
ch
as

carbon
tetrachloride
for

wiping

Raise

the
oil

tcmperalure
by

op

erating
the

engine
and

shift
the
lever

to
D
to
increase

the
oil

pressure

The

spot
of
oil

lcakage
will
then
be

found
more

easily

Note
As
oil

leakage
from
the
breaih

er
does
not
take

place
except
when

running
at

high
speed
it
is

impos

sible
to
locate
this

leakage
with

vehicle

stationary

CHECKING
ENGINE
IDLING

REVOLUTION

The

engine
idling
revolution
should

be

properly
adjusted

If
the

engine
revolution
is

too
low

the

engine
does
not

operate
smoothly

and
if
too

high
a

strong
shock
or

creep
develops
when

changing
over

from
N
to
D
or

R

CHECKING
AND
ADJUSTING

KICK

DOWN

SWITCH
AND

DOWNSHIFT

SOLENOID

When

the
kickdown

operation
is

not

made

properly
or
the

speed
chang

ing
point
s
too

high
check
the
kick

down
switch
downshift
solenoid
and

wiring
between
them
When
the

igni

li
n

key
is

pqsitioned
a
t

the
I

st

stage

nd
the
accelerator

pedal
is

depressed

deeply
the
switch
contact
should
be

closed
and
the
solenoid
should
click
If

it
does
not
click
it
indicates
a
defect

Then
check
each

part
with
the

testing

instruments
See

Figure
ATl09

d

I

t

AT10S

Fig
AT
109

Downshift
solenoid

Note
Watch
for
oil

leakage
from

transmission
case

AT
4Q
INSPECTION
AND

ADJUSTMENT
OF
MANUAL

LINKAGE

The

adjustmcnt
of

manual

linkage

is

equaUy
important
as

Inspection
of

Oil
Level
for
the
automatic
transmis

sion
Thereforc

great
care
should
be

exercised
because
incorrect

adjustment

will

rcsult
in
the
brcakdown
of
the

transmission

Inspection

Pull
the
selector
lever
toward

you

and
turn
it

as
far
as
P

to
I

range

wherc
clicks
will
be
felt

by
the
hand

This
is
the

detcnt
of
manual
valve
in

the
valve

body
and
indicates
th

correct

position
of
the

lever

Inspect
whether

the

pointer
of

selector
dial

corresponds
to
this

point

and
also
whether
the
lever
comes

in

alignment
with
the

stepping
of

posi

tion

plate
when
it
is
released

Adjustment

This

procedure
can
be

accomplish

ed

by
refcrring
to

page
AT
35

for

Removal
and
Installa
tion

CHECKING
AND

ADJUSTING

INHIBITOR
SWITCH

The
inhibitor
switch

lights
the
re

verse

lamp
in

the

range
R
of
the

transmission

operatio
l
and
also

rotates

the
starter
motor
in
the

ranges
N

and
P

CD

@
b
ell

If

L
t

7
4l

@

1l

j7
@
@

@
dl

AT109

6
Washer

7
Nut

8
Inhibitor
switch

9
Range
select
lever
t
Inhibitor
switch

2
Manual
shaft

3
Washer

4
Nut

5
Manual

plate

Fig
AT
110
Construction

of
inhibitor

switch

Using
the

tester
check
the

two

black

yellow
BY
wires
from
the
in

hibitor
switch
in
the

ranges
N

and

I
and
the

tw
re
d

black

RBj
wir
s

in

the

range
R
for

continuity
Turn

range
select
lever
in
both

directions

from

each
lever
set

position
and
check

each

continuity

range
It

is
normal
if

the

electricity
is

on
while
the
lever
is

within
an

angle
of
about
30

on
both

sides
from
each
lever
set
line
How

ever
if
its

continl
ity

range
is
obvious

ly
unequal
on

both
sides

adjustment
is

required

If

any
malfunction
is

found
un

screw
the

fastening
nut
of
the

range

selector
lever

and
two

fastening
bolts

of
the
switch

body
and
then
remove

the
machine
screw
under
the
switch

body
Adjust
the
manual
shaft
correct

ly
to
the

position
N

by
means
of
the

selector
lever

When
the

slot
of
the

shaft

becomes
vertical
the
detent

works
to

position
the
shaft

correctly

with
a

clicking
sound

MSlVe
the

switch

slightly
asj
Je
so

that
the
screw
hole
will
be

aligned

with
the

pin
hole
of
the
internal
rotor

combined
with
the
manual
shaft
and

check
their

alignment
by
inserting
a

1
5
mm
0
059
in
diameter

pin
into

the
holes
If

the

alignment
is
correct

fasten

the
switch

body
with
the
bolts

pull
out
the

pin
tighten

up
the
screw

in

the
hole
and
fasten
the
selector

lever
as
before
Check
the

continuity

again
with
the
tester
If

the
malfunc

tion
still

remains

replace
the
inhibitor

switch
Chcck
whether
the

reverse

lamp

and
the
starter
motor

operate
normal

ly
in
these

ranges
If
Ihere
is

any

lrouble

first
check
the

linkage
If

no

fault
is
found
in

the

linkage
check
the

inhibitor
switch

Separate
the
manual
lever
from
Ihe

remote
control
selector

rod
and
turn

the

range
selcct

lever
to

N

Note

In
the

position
N

the
slot
of

the

manual
shaft

is
vertical

STALL
TEST

The

purpose
of
this
test
is
to
check

the
transmission

and

engine
for
trou

ble

by
measuring
the
maximum
num

bers
of
revolutions
of

the

engine
while
Automatic

Transmission

vehicle
is
held
in
a

stalled

condition

The
carburctor
is
in

full
throttle

opera

tion
with

the
selector
lever
in

ranges

f
2

and
I

respectively
Com

pare
the

measured
results
with
the

slandard

values

Components
to

be
tested

and

test

items

I
Clutches
brake

and
band
in
trans

mission
for

slipping

2

Torque
converter

for

proper
fune

tioning

3

Engine
for
overall

properly

STALL
TEST

PROCEDURES

Before

Icsting
c
heck
the

engine
oil

and

torque
converter

oil
warm

up
the

engine
cooling
water
to
suitable
tem

perature
by
running
at

1
200

rpm
with

the
selector
lever
in

the

range
P
for

several
minutes
Warm

up
the

torque

converter
oil
to
suitable

temperature

6010
1000C
140
to

2l20F

I

Mount
the

engine
tachometer
at
a

location
that
allows

good
visibility

fro

the
dri
er
s
seat
and

put
a
mark

on

specified
revolutions
on
the
meter

2

Secure
the
front
and
rear
wheels

with
chocks
and

apply
the
hand
brake

Be
sure
to

depress
the
brake

pedal

fumly
with
the
left
foot
before
de

pressing
the
accelerator

pedal

3
Throw
the
selector
lever
into

the

range
1

4

Slowly
depress
the
accelerator

pedal
until
the

throttle
valvc
is

fully

opened

Quickly
read
and
record
the

engine
revolution
when

the

engine

begins
to
rotate

steadily
and
then

release
the
accelerator

pedal

5

Shift
the
selector
lever
to
N

and

operate
the

engine
at

approxi

mately
1
200

rpm
for
more
than
one

minute

to
cool
down
the

torque
con

ver
ter
oil

and
coolant

6

Make
similar
stall
tests
in

ranges

2
I
and
RIO

Note
The
stall
test

operation
as

speci

f
d
in
item
4

should
be

I
l3de

wiihin
five
seconds
If
it

takes
too

long
the
oil
deteriorates
an

the

clutches
brake

and
band
are
ad

versely
affected
Sufficient
cooling

time
should
be

given
between
each

AT
5O
test
for
the
four

ranges
0
2

I
and
R

JUDGEMENT

High
stall
revolution
more

than

standard
revolution

If
the

engine
revolution
in
stall

condition
is

higher
than
the
standard

values
it

indicates
that
one

or
more

clutches
in

the
transmission
are

slipping
and
therefore
no
further
test

is

required

For
the

following
abnormalities

the

respective
causes
are

presumed

High

rpm
in

all

ranges
low
Iine

pressure

High
rpm
in
D
2
and
I

and

normal

rpm
in
R
Rear
clutch

slipping

High
rpm
in
0

and

normal

rpm
in
I

clutch

slipping

High
rpm
in
R

only
Front

clutch
or
low
and
reverse

brake

slipping

To

determine
which
is

slipping

front
clutch
or
low

and
reverse
brake

a
road
test
is
nceded

If
whilc

coasting
after

starting

with
the
lever
in
1

range
engine

braking
does

not
work

properly
the

low
and

reverse
brake
is

slipping

Otherwise
the
front
clutch
is

slipping

Slipping
of
the
band
brake
is

diffi

cult
to
ascertain

However
if
it

occurs

with
the
lever
in
2

range

engine

revolution
increases

Jp
to
thesarne

level
as
in

I

strange
It

is

impossible

to
check

it
in
the
stall
test
2
and

One

way

2
Standard
stall
revolution

If
the

engine
revolution
in

stall

condition
is
within

the
standard

values
the
control
elements
are

nor

mally

operating
in
the

ranges
0

2
I

and
R

Also

tIle

engine
and
one

way

clutch
of
the

torque
converter
are

normal
in

performance
and

operation

The
one

way
clutch
of

the

torque

converter
however
sometimes

sticks

This
is
determined
in

the
road
test

3
Lower
stall
revolution
than
stand

ard
revolution

If
the

engine
revolution
in
stall

condition
is

lower
than
the
standard

CHECKING
SPEED

CHANGING
CONDITION

The
driver
s

feeling
during
gear

changes
should
also
be
checkedatten

tively

I
A

sharp
shock
or
unSffioothness
is

felt

during
a

gear
change

2
A

gear
change
is
made
with

a

long

and

dragging
feeling

These
indicate
that

the
tIuottle

pressure
is
too
low
or
some
valve

connected
to
the

throttle
is

faulty
h
k

100
1
1

2
I
2

J

I

1

2
I

I

I
2
3

oo
I

c

I

E

I

I

300

I

Z
5

L

mmHg

t
1

400

I

I

1

Output
shaft

speed
rpm

20
30
40

50
60
70
80
90100
00

io
3
0
40
0
60

Vehicle

speed
R
4

315
r

0
321
6
00
14

ATll0

Fig
AT
111
Shift
IChedule
Automatic
Transmission

SHI

SCHEDULE

500

CHECKING
ITEMS
DURING

km
hO
1O

SPEED

CHANGE

I

In
D

range
gear
changes

DI

D2
D3
are
effected
In
R

range
the

speed
does

not
increase

2
The
kickdown

operates

properly

3

By
moving
the
lever
from
D
to

I

gear
changes
D

2
1

2
1

are
effected
In
the

ranges
12
and

I
the

engine
braking
works

prop

erly

4
In
I
the

speed
does
not
in

crease

5
Should
be

quickly
fixed

at
2

range

6
In

P
vehicle
can
he

parked

properly

If

any
malfunction
occurs
in
second

gear
during
the
road
test
that
is

if

vehicle
shakes

drags
or
slings
while

shifting
up
from
D

directly
to

D
or
in

shifting
up
from
D

to

D2
the
brake
band
should
be
ad

justed
If

these
troubles
remain
after

the
brake
band
is

adjusted
check
the

servo

piston
seal
for
oil

leakage
MPH
Ii
io

LINE
PRESSURE
TEST

When

any

slipping
occurs
in
clutch

or
brake
or
the
feeling

during
a

speed

change
is
not
correct
the
line

pressure

must
be
checked

Measuring
line

pressure
is
done

by
a

pressure
gauge
attached
to
two

pres

sure

measuring
holes
after

removing

blind

plugs
located
at

transmission

case
See

Figure
AT
112

The
line

pressure
measurement
is

begun
at

idling
and
taken

step
by
step

by
enlarging
the
throttle

opening

I
A

sharp
shock
in

up
shifting
or

too

high
changing
speeds
are
caused

mostly

by
too

high
throttle

pressure

2

Slipping
or

incapability
of

opera

tion
is

mostly
due
to
oil

pressure

leakage
within
the

gear
trains
or

spool

valve

AT
S2
3

3SA

000

t
I

1
I

c
l

1

c

7
D

jf
o

CV

ATl13

1

Lige

pressure

2

Governor
feed

3

SerVo
release

pressure

Fig
AT
112

MeCJ
uring
line

preuure

Automatic
Transmission

LINE
PRESSURE
GOVERNOR
FEED
PRESSURE

At

cut
back

point
After
cut
back

Throttle

opening
under

approximately
over

approximately

15

kmfh

10
MPH
35
kmfh
22
MPH

Unit

mmHg
Unit

kgfcm2
psi
Unit

kgfcm2
psi

Full
throtlle
0
9
4

to
11
0

134

to
156
5
5
to
6
5
78
to

92

Minill1um
throttle
450
3

0
to
4

0
43to
57
3
0
to
4
0

43
to

57

Fulllhrotlle
0
10
0

to
12
0

142
to

171
5

5
to
7
0

78

to
100

Minimum

throttle
450
6
0
to
12
0
85to171
5
5
to
7
0
78
to
100

Full
throtlle
0
14
0
to
16

0
199
to

228
14
0
to
16
0
199

to
228

Minimum
throttle
450
3
0
to
5
5
43
to
78
3
0
to

5
5
4
lo

78
Range

D

2

R

Notes
a
The
line

pressure
during

idling
corresponds
to
the
oil

pressure
before
cut
down
at

minimum
throttle

b
The
oil

pressure
After
cut
back
means
that
after
the

pressure
modifier
valve
has

operated

JUDGEMENT
IN
MEASURING

LINE
PRESSURE

Low

idling
line

pressure
in
the

ranges
D
2
I
R
and
pH

This
can
be
atlributed
to
trouble
in

the

pressure
supply
system
or
too
low

output
of

power
caused

by

I
A
worn
oil

pump

2
An

oil

pressure
leak
in
the
oil

pump
valve

body
or
case

3
A

sticking
regulator
valve

2
Low

idling
line

pressure
in
cer

tain

ranges
only

This
is

presumably
caused

by
an
oil

leak
in
the
devices
or
circuits
con

nected
to
the
relevant

ranges

I
When

there
is
an
oil
leak
in

the

rear
clutch
and

governor
the
line

pressure
in
D
2
and
I

are
low

but
the

pressure
is

norrrial
in
R

2
When
an
oil
leak
occurs
in
the

low
and

reverse
brake
circuit
the
line

pressure
in
R
and
P
are
low
but

the

pressure
is
normal
in
D

2
and

I

3

High
idling
line

pressure

This
is

presumably
caused

by
an

increased
vacuum
throttle

pressure

owing
to
a
leak
in

the
vacuum
tube
or

dia

phragm
or

by
an
increased
line
pressure
due
to
a

sticking
regulator

valve

Vacuum
leakage
is
checked

by

directly
measuring
the

negative
pres

sure
after

removing
the
vacuum

pipe

A

puncture
of
the
vacuum
dia

phragm
can
be

easily
ascertained

because
the

torque
converter
oil
is

absorbed
into
the

engine
and
the

exhaust

pipe
emits
white

smoke

4

Items
to
be
checked
when
the

line

pressure
is

increasing

In

this
check
the
line

pressure

should
be
measured
with
vacuums
of

450

mmHg
and
0

mmHg
in
accordance

with
the
stall
test

procedure

I
If

the
line

pressure
do
not
n

crease

despite
the
vacuum
decrease

check
whether
the

vacuum
rod
is

incorporated

2
If
the
line

pressure
do
not
meet

the
standard

it
is
caused

mostly
by
a

sticking
pressure
regulating
valve

pres

sure

regulating
valve

plug
or

amplifier

TROUBLE
SHOOTING

CHART

INSPECTING
ITEMS

1

Inspection
with
automatic
trans

mission
on
vehicle

AT
53
A

Oil
level

B

Ra
lge
select

linkage

C
Inhibitor
switch
and

wiring

D
Vacuum

diaphragm
and

piping

E
Downshift
solenoid
kickdown

switch
and

wiring

F

Engine
idling

rpm

G
Oil

pressure
throttle

H

Engine
stall

rpm

I
Rear
lubrication

J
Control
valve
manual

K
Governor
valve

L
Band
servo

M
Transmission
air
check

N
Oil

quantity

o

Ignition
switch
and
starter
motor

P

Engine

adjustment
and
brake
in

spection

2

Inspection
after

inspecting
auto

matic
transmission

on
vehicle

m
Rear
clutch

n
Front
clutch

q
Band
brake

r
Low
and
reverse
brake

s
Oil

pump

t

Leakage
of
oil

passage

u
One

way
clutch
of

troque
coilVerter

v
One

way
clutch
of
transmission

w
Front
clutch
check
ball

x
Parking

linkage

y
Planetary

gear

Automatic

Transmission

TROUBLE
SHOOTING
CHART
FOR
3N718
AUTOMATIC
TRANSMISSION

The
number
shown
beluw

indicates
the

sequence
in

which
the

checks
should
be
taken

up

Trouble
ABeD

EFGHIIJKL
MNOP

tnnqr
stuv

wxy

ngine
does
not
start
in
N
P

ranges
2

3
1

Engine
starts
in

other

range
than
N

and

P
1
2

Sharp
shock
in

shifting
from
N

to

0

range

Vehicle
will
not

run
in
D

range
bul

I

TUns
in
2u
l
and
R

ranges
2
4

@

3

5
6
3
7

@
@
2
1
3

Vehicle

will
not

run
in
0
1

2

ranges
bul
runs
in
R

range
1
2

Clutch

slips
Very
poor
acceleration
4

Vehicle
will
nol
run
in
R

range
bul

runs
in
0

2
and
I

r

nges
1
2

Iukh

slips
Very
poor
acceleration
3

5
6
4

@@
1
@
@

Vehicle
will
not
run
in

any
range
1
2
3
5
6
4
1
@
@

Clutches

or
brakes

slip
somewhat

1
2
6

I
3
5
7
4

@@

in

starting

Vehicle
runs
in
N

range
I
3
2

Maximum

speed
not
allained

1
2
4
5
7
6
3
8

OO
I@

Acceleration

poor

Vehicle
braked

by
Ihrowing
Icver
inlo
3

2
1

@

I
@

R

range

I

Excessive

creep
1

No

creep
al

all
I
2
3
5
4

@@

@
1

Failure
10

dumge
gear
from
2nd

I
2
3
5
6
8
7
4

@
@

to
3rd

Failure

tllchJllgC
gear
from
1
1

1
2
3
5
6
8
7
4

@
@
@

to
2ud

Too

high
a

gear
change
poinl
from

I

sC
to
2nd
from

2nd
to
1
2
3
5
6
4
1

3rd

Gear

change
directly
from

lsl
to

2
4

3
1
@

@

rd
occurs

AT

54

Automatic
Transmission

TROUBLE
SHOOTING
GUIDE
FOR
3N71B
AUTOMATIC

TRANSMISSION

Order
Test
item

Checking
Oil
level

gauge

2
Downshift
solenoid

3

Manuallinkage

L

4
Inhibitor
switch

5

Engine
idling
rpm

6
Vacuum

pressure
of

vacuum

pipe

7

Operation
in
each

range

8

Creep
of
vehicle

Stall
test
I

Oil

pressure
before

tesling
1

2
Stall
test

3
Oil

pressure
after

testing

Road
test
Slow
acceleration

I

st
2nd

2nd
3rd

2

Quick
acceleration

lst
2nd

2nd
3rd

3

Kick
down

operation

3rd
2nd

or

2nd
1st
Procedure

Check

gauge
for
oil
level
and

leakage
before
and

after
each

test

Check
for
sound
of

operating
solenoid
when

depressing

accelerator

pedal
fully
with

ignition
key
ON

Check

by

shifting
into

P
lR
IN
D
2
and
I

ranges
with
selector
lever

Check

whether
starter

operates
in
N
and
p

ranges
only

and
whether
reverse

lamp
operates
in

R
range
only

Check
whelher

idling
rpm
meet

standard

Check
whether

vacuum

pressure
is

more
than
450

mmHg

in

idling
and
whether
it

decreases
with

increasing
rpm

Check
whether
transmission

engages
positively
by
shifting

N
0
N

2
N

l
I
and
N
R

range

while

idling
with
brake

applied

Check
whether

there
is

any
creep
in
D
2

R

ranges
and

Measure
line

pressures
in
D
2
I
and
R

range
while

idling

Measure

engine

rpm
and
line

pressure
in
D
2
I

and

R

ranges
during
full
throttle

operati
n

Notes

a

Temperature
of

torque
converter
oil
used
in
test
should

be
from
600

to
1000C
1400
to
2120F
i
e

sufficiently

warmed

up
but
not
overheated

b
To
cool
oil

between
each
stall
test
for
D
2
I

and
R

ranges
idle

engine
i
e

rpm
at
about
1
200

rpm
for
more
than
1
minute
in
P

range
Measurement

time
must
not
be
more
than
5
seconds

Same
as
item
I

Check
vehide

speeds
and

engine
cpm
in

shifting
up
Ist

2nd

range
and
2nd
Jo3rd
range
while

running
with
lever
in

D

range
and

engine
vacuum

pressure
of
about
200

I11I1lHg

Same

as
item
1
above

except
with

engine
vacuum
pressure

of
0

mmHg
i

e
in

position
just
before
kickdown

Check
whether
the
kickdown

operates
and
measure
the
time

delays
while

running
at
30
40
50
60
70
km
h
18
25
30

37
43
MPH
in

D3
range

AT

57

Automatic
Transmission

Order
Test
item

4
Shift
down

Dr
O2
0

5

Shift
down

DJ
12
1

6
Shift
down

DJ
2

7
Shift

up

I

12

8
Shift

up
or
down
when

start

iog
in

2

range

9

Parking

Others
Abnormal
shock
oil

leakage
Procedure

Check
vehicle

speeds
and

engine
rpm
in

shifting
down
from

3rd
2nd
I

st

sequentially
while

coasting
with

accelerater

pedal
released
in

D3
range
and

engine
vacuum

pressure
of
about
450

mmHg

Check
for

shifting
down

OJ
12
and

engine
braking
and

further
for

shifting
down

12
I
and

engine
braking
after

shifting
the
lever
into

I

range
with
the
accelerator

pedal

released
and
the

engine
vacuum

pressure
of
0

mmHg
while

driving
at
about
50
km
h

30
MPH
in

OJ
range

Check
for

quick
shifting
down

0
2
and

engine
biaking

after

shifting
the

lever
into
2

range
while

driving
at
about

50
km
h
30
MPH
in

OJ
range

Further
check
for

locking
of
the

transmission
in

2nd

gear

ratio

regardless
of
vehicle

speed

Check
for
failure
of
the
transmission
to
shift

up
during

acceleration
when

starting
in
I

range

Check
the
transmission

for
not

shifting
up
or
down

during

acceleration
or
deceleration
when

starting
in

2

rang

Confirm
that
vehicle
will
not
move
on

grade
when

shifting

to

P

range

Enter
into
record
conditions
observed

during
these
tests

such
as

gear
noise

abnormal
clutch
noise
and

acceleration

performance

AT
58