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Nissan 240SX - Automatic Transmission (Section AT) (2000 year). Instruction - part 1

AUTOMATIC TRANSMISSION

SECTION

CONTENTS

PRECAUTIONS ...............................................................4

Supplemental Restraint System (SRS)

............................................................................4

Precautions ..................................................................4
Service Notice or Precautions .....................................5
Wiring Diagrams and Trouble Diagnosis.....................6

PREPARATION ...............................................................7

Special Service Tools ..................................................7

A/T FLUID ........................................................................9

Checking A/T Fluid ......................................................9
Changing A/T Fluid ......................................................9

OVERALL SYSTEM ...................................................... 11

A/T Electrical Parts Location ..................................... 11
Circuit Diagram ..........................................................12
Cross-sectional View .................................................13
Hydraulic Control Circuit............................................14
Shift Mechanism ........................................................15
Control System ..........................................................24
Control Mechanism....................................................25
Control Valve .............................................................30

ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION ...............................................................32

CONSULT-II ...............................................................32
Diagnostic Procedure Without CONSULT-II..............37

TROUBLE DIAGNOSIS - INTRODUCTION..................42

Introduction ................................................................42
Work Flow..................................................................46

TROUBLE DIAGNOSIS - BASIC INSPECTION ...........48

A/T Fluid Check .........................................................48
Stall Test ....................................................................48
Line Pressure Test.....................................................51
Road Test...................................................................52

TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION ...............................................................70

Symptom Chart..........................................................70
TCM Terminals and Reference Value........................82

TROUBLE DIAGNOSIS FOR POWER SUPPLY..........86

Wiring Diagram - AT - MAIN......................................86
Diagnostic Procedure ................................................87

TROUBLE DIAGNOSIS FOR VHCL SPEED
SEN.A/T (REVOLUTION SENSOR)..............................89

Description .................................................................89
Wiring Diagram - AT - VSSA/T ..................................91
Diagnostic Procedure ................................................92
Component Inspection...............................................93

TROUBLE DIAGNOSIS FOR VHCL SPEED
SEN.MTR .......................................................................95

Description .................................................................95
Wiring Diagram - AT - VSSMTR................................96
Diagnostic Procedure ................................................97

TROUBLE DIAGNOSIS FOR THROTTLE POSI
SEN ................................................................................98

Description .................................................................98
Wiring Diagram - AT - TPS......................................100
Diagnostic Procedure ..............................................101
Component Inspection.............................................105

TROUBLE DIAGNOSIS FOR SHIFT SOLENOID/V
A ...................................................................................106

Description ...............................................................106
Wiring Diagram - AT - SSV/A ..................................108
Diagnostic Procedure ..............................................109
Component Inspection............................................. 110

TROUBLE DIAGNOSIS FOR SHIFT SOLENOID/V
B ................................................................................... 111

Description ............................................................... 111
Wiring Diagram - AT - SSV/B .................................. 113
Diagnostic Procedure .............................................. 114
Component Inspection............................................. 115

TROUBLE DIAGNOSIS FOR OVERRUN CLUTCH
S/V................................................................................ 116

Description ............................................................... 116
Wiring Diagram - AT - OVRCSV.............................. 117
Diagnostic Procedure .............................................. 118
Component Inspection............................................. 119

TROUBLE DIAGNOSIS FOR T/C CLUTCH SOL/V ...120

Description ...............................................................120
Wiring Diagram - AT - TCV......................................122
Diagnostic Procedure ..............................................123

IDX

Component Inspection.............................................124

TROUBLE DIAGNOSIS FOR BATT/FLUID TEMP
SEN ..............................................................................125

Description ...............................................................125
Wiring Diagram - AT - BA/FTS ................................127
Diagnostic Procedure ..............................................128
Component Inspection.............................................131

TROUBLE DIAGNOSIS FOR ENGINE SPEED SIG ..132

Description ...............................................................132
Wiring Diagram - AT - ENGSS ................................133
Diagnostic Procedure ..............................................134

TROUBLE DIAGNOSIS FOR LINE PRESSURE
S/V................................................................................136

Description ...............................................................136
Wiring Diagram - AT - LPSV....................................138
Diagnostic Procedure ..............................................139
Component Inspection.............................................140

TROUBLE DIAGNOSIS FOR CONTROL UNIT
(RAM), CONTROL UNIT (ROM) .................................142

Description ...............................................................142
Diagnostic Procedure ..............................................143

TROUBLE DIAGNOSIS FOR CONTROL UNIT
(EEPROM)....................................................................144

Description ...............................................................144
Diagnostic Procedure ..............................................145

TROUBLE DIAGNOSES FOR SYMPTOMS ...............146

Wiring Diagram - AT - NONDTC .............................146
1. POWER Indicator Lamp Does Not Come On.....149
2. POWER or SNOW Indicator Lamp Does Not
Come On .................................................................150
3. O/D OFF Indicator Lamp Does Not Come On....151
4. POWER Indicator Lamp Does Not Come On.....152
5. Engine Cannot Be Started In

″

and

″

Position ....................................................................153
6. In

″

Position, Vehicle Moves Forward Or

Backward When Pushed .........................................154
7. In

″

Position, Vehicle Moves ...........................155

8. Large Shock.

″

Position .......................157

9. Vehicle Does Not Creep Backward In

″

Position ....................................................................159
10. Vehicle Does Not Creep Forward In

″

Position.........................................................162

11. Vehicle Cannot Be Started From D

.................165

12. A/T Does Not Shift: D

..................................................168

13. A/T Does Not Shift: D

-> D

.............................171

14. A/T Does Not Shift: D

-> D

.............................174

15. A/T Does Not Perform Lock-up .........................177
16. A/T Does Not Hold Lock-up Condition ..............179
17. Lock-up Is Not Released...................................181
18. Engine Speed Does Not Return To Idle (Light
Braking D

-> D

).....................................................182

19. Vehicle Does Not Start From D

.......................184

20. A/T Does Not Shift: D

-> D

, When

Overdrive Control Switch

″

OFF

″

...............185

21. A/T Does Not Shift: D

Position.........................................186

22. A/T Does Not Shift: 2

Position .........................................187

23. Vehicle Does Not Decelerate By Engine
Brake........................................................................188
24. TCM Self-diagnosis Does Not Activate (PNP,
Overdrive Control, A/T Check and TP Switches
Circuit Checks) ........................................................189

A/T SHIFT LOCK SYSTEM.........................................198

Description ...............................................................198
Wiring Diagram - SHIFT -........................................199
Diagnostic Procedure ..............................................200
Component Check ...................................................202

KEY INTERLOCK CABLE ..........................................203

Removal...................................................................203
Installation................................................................203

SHIFT CONTROL SYSTEM ........................................204

Control Device .........................................................204

ON-VEHICLE SERVICE ..............................................205

Control Valve Assembly and Accumulators.............205
Revolution Sensor Replacement .............................205
Rear Oil Seal Replacement.....................................206
Parking Pawl Components Inspection.....................206
Park/Neutral Position Switch Adjustment ................206
Manual Control Linkage Adjustment........................207

REMOVAL AND INSTALLATION ...............................208

Removal...................................................................208
Installation................................................................209

OVERHAUL ................................................................. 211

Components............................................................. 211
Oil Channel ..............................................................213
Locations of Needle Bearings, Thrust Washers
and Snap Rings .......................................................214

DISASSEMBLY............................................................215
REPAIR FOR COMPONENT PARTS .........................226

Oil Pump ..................................................................226
Control Valve Assembly...........................................230
Control Valve Upper Body .......................................236
Control Valve Lower Body .......................................241
Reverse Clutch ........................................................243
High Clutch ..............................................................246
Forward and Overrun Clutches ...............................249
Low & Reverse Brake..............................................253
Forward Clutch Drum Assembly..............................257
Rear Internal Gear and Forward Clutch Hub ..........259
Band Servo Piston Assembly ..................................262
Parking Pawl Components ......................................266

ASSEMBLY..................................................................268

CONTENTS

(Cont’d)

AT-2

Assembly (1)............................................................268
Adjustment ...............................................................276
Assembly (2)............................................................279

A/T FLUID COOLER SYSTEM ...................................286

A/T Fluid Cooler.......................................................286

SERVICE DATA AND SPECIFICATIONS (SDS) .......288

General Specifications.............................................288
Shift Schedule..........................................................288
Stall Revolution........................................................288

Line Pressure...........................................................288
Return Springs.........................................................289
Accumulator O-ring..................................................290
Clutches and Brakes ...............................................290
Oil Pump and Low One-way Clutch ........................292
Total End Play..........................................................292
Reverse Clutch Drum End Play ..............................293
Removal and Installation .........................................293

IDX

CONTENTS

(Cont’d)

AT-3

Supplemental Restraint System (SRS) “AIR
BAG”

NMAT0253

The Supplemental Restraint System such as “AIR BAG” used along with a seat belt, helps to reduce the risk
or severity of injury to the driver and front passenger for certain types of collision. The SRS system composi-
tion which is available to NISSAN MODEL S15 is as follows:
The Supplemental Restraint System consists of driver air bag module (located in the center of the steering
wheel), front passenger air bag module (located on the instrument panel on passenger side), a diagnosis
sensor unit, warning lamp, wiring harness and spiral cable.
Information necessary to service the system safely is included in the RS section of this Service Manual.

WARNING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance should be per-
formed by an authorized NISSAN dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified with yellow harness connector.

SEF289H

Precautions

NMAT0003

Before connecting or disconnecting the TCM harness
connector, turn ignition switch “OFF” and disconnect
negative battery terminal. Failure to do so may damage
the TCM. Because battery voltage is applied to TCM even
if ignition switch is turned “OFF”.

AAT470A

When connecting or disconnecting pin connectors into or
from TCM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on TCM
pin terminal, when connecting pin connectors.

MEF040DA

Before replacing TCM, perform TCM input/output signal
inspection and make sure whether TCM functions prop-
erly or not. (Refer to AT-82.)

PRECAUTIONS

Supplemental Restraint System (SRS) “AIR BAG”

AT-4

Before proceeding with disassembly, thoroughly clean the out-
side of the transmission. It is important to prevent the internal
parts from becoming contaminated by dirt or other foreign mat-
ter.

Disassembly should be done in a clean work area.

Use lint-free cloth or towels for wiping parts clean. Common
shop rags can leave fibers that could interfere with the opera-
tion of the transmission.

Place disassembled parts in order for easier and proper
assembly.

All parts should be carefully cleaned with a general purpose,
non-flammable solvent before inspection or reassembly.

Gaskets, seals and O-rings should be replaced any time the
transmission is disassembled.

It is very important to perform functional tests whenever they
are indicated.

The valve body contains precision parts and requires extreme
care when parts are removed and serviced. Place disas-
sembled valve body parts in order for easier and proper
assembly. Care will also prevent springs and small parts from
becoming scattered or lost.

Properly installed valves, sleeves, plugs, etc. will slide along
bores in valve body under their own weight.

Before assembly, apply a coat of recommended ATF to all
parts. Apply petroleum jelly to protect O-rings and seals, or
hold bearings and washers in place during assembly. Do not
use grease.

Extreme care should be taken to avoid damage to O-rings,
seals and gaskets when assembling.

After overhaul, refill the transmission with new ATF.

When the A/T drain plug is removed, only some of the fluid is
drained. Old A/T fluid will remain in torque converter and ATF
cooling system.
Always follow the procedures when changing A/T fluid. Refer
to “Changing A/T Fluid”, AT-9.

Service Notice or Precautions

NMAT0004

FAIL-SAFE

NMAT0004S01

The TCM has an electronic Fail-Safe (limp home mode). This allows the vehicle to be driven even if a major
electrical input/output device circuit is damaged.
Under Fail-Safe, the vehicle always runs in third gear, even with a shift lever position of “1”, “2” or “D”. The
customer may complain of sluggish or poor acceleration.
When the ignition key is turned “ON” following Fail-Safe operation, POWER indicator lamp blinks for about 8
seconds. [For “SELF-DIAGNOSTIC PROCEDURE (Without CONSULT-II)”, refer to AT-37.]
The blinking of the POWER indicator lamp for about 8 seconds will appear only once and be cleared. The
customer may resume normal driving conditions.
Always follow the “WORK FLOW” (Refer to AT-46).

IDX

PRECAUTIONS

Precautions (Cont’d)

AT-5

The SELF-DIAGNOSIS results will be as follows:
The first SELF-DIAGNOSIS will indicate damage to the vehicle speed sensor or the revolution sensor.
During the next SELF-DIAGNOSIS, performed after checking the sensor, no damages will be indicated.

TORQUE CONVERTER SERVICE

NMAT0004S04

The torque converter should be replaced under any of the following conditions:

External leaks in the hub weld area.

Converter hub is scored or damaged.

Converter pilot is broken, damaged or fits poorly into crankshaft.

Steel particles are found after flushing the cooler and cooler lines.

Pump is damaged or steel particles are found in the converter.

Vehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses
have been made. (Converter clutch material may be glazed.)

Converter is contaminated with engine coolant containing antifreeze.

Internal failure of stator roller clutch.

Heavy clutch debris due to overheating (blue converter).

Steel particles or clutch lining material found in fluid filter or on magnet when no internal parts in unit are
worn or damaged — indicates that lining material came from converter.

The torque converter should not be replaced if:

The fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.

The threads in one or more of the converter bolt holes are damaged.

Transmission failure did not display evidence of damaged or worn internal parts, steel particles or clutch
plate lining material in unit and inside the fluid filter.

Vehicle has been exposed to high mileage (only). The exception may be where the torque converter clutch
dampener plate lining has seen excess wear by vehicles operated in heavy and/or constant traffic, such
as taxi, delivery or police use.

Wiring Diagrams and Trouble Diagnosis

NMAT0005

When you read wiring diagrams, refer to the followings:

GI-30, “HOW TO FOLLOW TROUBLE DIAGNOSES”.

EL-7, “POWER SUPPLY ROUTING” for power distribution circuit.

When you perform trouble diagnosis, refer to the followings:

GI-31, “HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES”.

GI-20, “HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT”.

PRECAUTIONS

Service Notice or Precautions (Cont’d)

AT-6

Special Service Tools

NMAT0006

Tool number
Tool name

Description

ST2505S001
Oil pressure gauge set
1 ST25051001
Oil pressure gauge
2 ST25052000
Hose
3 ST25053000
Joint pipe
4 ST25054000
Adapter
5 ST25055000
Adapter

NT097

Measuring line pressure

ST07870000
Transmission case stand

NT421

Disassembling and assembling A/T
a: 182 mm (7.17 in)
b: 282 mm (11.10 in)
c: 230 mm (9.06 in)
d: 100 mm (3.94 in)

KV31102100
Torque converter one-
way clutch check tool

NT098

Checking one-way clutch in torque converter

ST25850000
Sliding hammer

NT422

Removing oil pump assembly
a: 179 mm (7.05 in)
b: 70 mm (2.76 in)
c: 40 mm (1.57 in) dia.
d: M12 x 1.75P

KV31102400
Clutch spring compres-
sor

NT423

Removing and installing clutch return springs
a: 320 mm (12.60 in)
b: 174 mm (6.85 in)

KV381054S0
(ST33290001)
Puller

NT414

Removing rear oil seal
a: 250 mm (9.84 in)
b: 160 mm (6.30 in)

IDX

PREPARATION

Special Service Tools

AT-7

Tool number
Tool name

Description

ST33200000
Drift

NT091

Installing oil pump housing oil seal Installing rear
oil seal
a: 60 mm (2.36 in) dia.
b: 44.5 mm (1.752 in) dia.

PREPARATION

Special Service Tools (Cont’d)

AT-8

SMA514CA

SMA051D

Checking A/T Fluid

NMAT0254

Warm up engine.

Check for fluid leakage.

Before driving, fluid level can be checked at fluid temperatures
of 30 to 50°C (86 to 122°F) using “COLD” range on A/T fluid
level gauge.

Park vehicle on level surface and set parking brake.

Start engine and move selector lever through each gear posi-
tion. Leave selector lever in “P” position.

Check fluid level with engine idling.

Remove A/T fluid level gauge and note reading. If level is at
low side of either range, and fluid to the charging pipe.

Re-insert A/T fluid level gauge into charging pipe as far as it
will go.

Remove A/T fluid level gauge and note reading. If reading is
at low side of range, add fluid to the charging pipe.

Do not overfill.
4.

Drive vehicle for approximately 5 minutes in urban areas.

Re-check fluid level at fluid temperatures of 50 to 80°C (122
to 176°F) using “HOT” range on A/T fluid level gauge.

CAUTION:

Firmly fix the A/T fluid level gauge to the fluid charging pipe
using a stopper attached.

SMA853B

Check fluid condition.

If fluid is very dark or smells burned, refer to AT section for
checking operation of A/T. Flush cooling system after repair of
A/T.

If A/T fluid contains frictional material (clutches, bands, etc.),
replace radiator and flush cooler line using cleaning solvent
and compressed air after repair of A/T. Refer to LC-14, “Com-
ponents”.

SMA515C

Changing A/T Fluid

NMAT0255

Warm up A/T fluid.

Stop engine.

Drain A/T fluid from drain plug and refill with new A/T fluid.
Always refill same volume with drained fluid.

Fluid grade:

Genuine Nissan ATF or equivalent. Refer to MA-8,
“Fluids and Lubricants”.

Fluid capacity (With torque converter):

7.9

(7 Imp qt)

IDX

A/T FLUID

Checking A/T Fluid

AT-9

Drain plug:

: 29 - 39 N·m (3.0 - 4.0 kg-m, 22 - 29 ft-lb)

Run engine at idle speed for five minutes.

Check fluid level and condition. Refer to “Checking A/T Fluid”,
AT-9. If fluid is still dirty, repeat steps 2 through 5.

A/T FLUID

Changing A/T Fluid (Cont’d)

AT-10

A/T Electrical Parts Location

NMAT0007

SAT405K

IDX

OVERALL SYSTEM

A/T Electrical Parts Location

AT-11

Circuit Diagram

NMAT0008

TAT253

OVERALL SYSTEM

Circuit Diagram

AT-12

Cross-sectional View

NMAT0010

SAT125BA

IDX

OVERALL SYSTEM

Cross-sectional View

AT-13

Hydraulic Control Circuit

NMAT0011

SAT151K

OVERALL SYSTEM

Hydraulic Control Circuit

AT-14

Shift Mechanism

NMAT0012

The automatic transmission uses compact, dual planetary gear systems to improve power-transmission
efficiency, simplify construction and reduce weight.
It also employs an optimum shift control and superwide gear ratios. They improve starting performance and
acceleration during medium and high-speed operation.
Two one-way clutches are also employed: one is used for the forward clutch and the other for the low clutch.
These one-way clutches, combined with four accumulators, reduce shifting shock to a minimum.

CONSTRUCTION

NMAT0012S01

SAT509I

Torque converter clutch piston

Torque converter

Oil pump

Input shaft

Brake band

Reverse clutch

High clutch

Front pinion gear

Front sun gear

10. Front internal gear
11. Front planetary carrier
12. Rear sun gear
13. Rear pinion gear
14. Rear internal gear
15. Rear planetary carrier
16. Forward clutch

17. Forward one-way clutch
18. Overrun clutch
19. Low one-way clutch
20. Low & reverse brake
21. Parking pawl
22. Parking gear
23. Output shaft

FUNCTION OF CLUTCH AND BRAKE

NMAT0012S02

Clutch and brake components

Abbr.

Function

Reverse clutch 6

R/C

To transmit input power to front sun gear 9.

High clutch 7

H/C

To transmit input power to front planetary carrier 11.

Forward clutch 16

F/C

To connect front planetary carrier 11 with forward one-way
clutch 17.

Overrun clutch 18

O/C

To connect front planetary carrier 11 with rear internal gear 14.

Brake band 5

B/B

To lock front sun gear 9.

Forward one-way clutch 17

F/O.C

When forward clutch 16 is engaged, to stop rear internal gear
14 from rotating in opposite direction against engine revolution.

Low one-way clutch 19

L/O.C

To stop front planetary carrier 11 from rotating in opposite direc-
tion against engine revolution.

Low & reverse brake 20

L & R/B

To lock front planetary carrier 11.

IDX

OVERALL SYSTEM

Shift Mechanism

AT-15

CLUTCH AND BAND CHART

NMAT0012S03

Shift position

Reverse

clutch

High

clutch

For-

ward

clutch

Over-

run

clutch

Band servo

For-

ward

one

-way

clutch

Low

one-

way

clutch

Low &

reverse

brake

Lock-up

Remarks

2nd

apply

3rd

release

4th

apply

PARK

POSITION

REVERSE
POSITION

NEUTRAL

POSITION

D*4

1st

*1D

Automatic

shift

2nd

*1A

3rd

*1A

*2C

4th

*3C

1st

Automatic

shift

2nd

1st

Locks (held

stationary) in

1st speed

2nd

*1: Operates when overdrive control switch is being set in “OFF” position.
*2: Oil pressure is applied to both 2nd “apply” side and 3rd “release” side of band servo piston. However, brake band does not contract
because oil pressure area on the “release” side is greater than that on the “apply” side.
*3: Oil pressure is applied to 4th “apply” side in condition *2 above, and brake band contracts.
*4: A/T will not shift to 4th when overdrive control switch is set in “OFF” position.
*5: Operates when overdrive control switch is “OFF”.

: Operates.

A: Operates when throttle opening is less than 3/16, activating engine brake.
B: Operates during “progressive” acceleration.
C: Operates but does not affect power transmission.
D: Operates when throttle opening is less than 3/16, but does not affect engine brake.

OVERALL SYSTEM

Shift Mechanism (Cont’d)

AT-16

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