2001 NISSAN ALMERA transmission

SMA827CA
Checking A/T FluidNJAT02281. Warm up engine.
2. Check for fluid leakage.
3. Before driving, fluid level can be checked at fluid temperatures
of 30 to 50ÉC (86 to 122ÉF) using ªCOLDº range on dipstick.
a. Park vehicle on level surface and set parking brake.
b. Start engine and move selector lever through each gear posi-
tion. Leave selector lever in ªPº position.
c. Check fluid level with engine idling.
d. Remove dipstick and note reading. If level is at low side of
either range, and fluid to the charging pipe.
e. Re-insert dipstick into charging pipe as far as it will go.
f. Remove dipstick 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.
5. Re-check fluid level at fluid temperatures of 50 to 80ÉC (122
to 176ÉF) using ªHOTº range on dipstick.
SMA853B
6. 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-16, ªRadia-
torº.
SMA027D
Changing A/T FluidNJAT02291. Warm up A/T fluid.
2. Stop engine.
3. Drain A/T fluid from drain plug and refill with new A/T fluid.
Always refill same volume with drained fluid.
Fluid grade:
Nissan Matic ªDº or Genuine Nissan Automatic
Transmission Fluid. Refer to ªRECOMMENDED FLU-
IDS AND LUBRICANTSº, MA-16.
Fluid capacity (With torque converter):
7.0!(6-1/8 Imp qt)
Drain plug:
: 29 - 39 N´m (3.0 - 4.0 kg-m, 22 - 29 ft-lb)
4. Run engine at idle speed for five minutes.
5. Check fluid level and condition. Refer to ªChecking A/T Fluidº.
If fluid is still dirty, repeat steps 2 through 5.
A/T FLUID
Checking A/T Fluid
AT-15

CLUTCH AND BAND CHARTNJAT0013S04
Shift positionReverse
clutch
5High
clutch
6For-
ward
clutch
15Over-
run
clutch
17Band servo
Forward
one-way
clutch
16Low
one-
way
clutch
18Low &
reverse
brake
19Lock-up Remarks
2nd
apply3rd
release4th
apply
PPARK
POSITION
RjjREVERSE
POSITION
NNEUTRAL
POSITION
D*41stj*1D B B
Automatic
shift
1Û2Û3
Û4 2ndj*1AjB
3rdjj*1A *2C C B *5j
4thjC *3C Cjj
21stjDBBAutomatic
shift
1Û2 2ndjAjB
11stjjBjLocks (held
stationary)
in 1st
speed
1Ü2 2ndjjjB
*1: Operates when overdrive control switch is set in ªOFFº position.
*2: Oil pressure is applied to both 2nd ªapplyº side and 3rd ªreleaseº side of band servo piston. However, brake band does not contract
because oil pressure area on the ªreleaseº side is greater than that on the ªapplyº side.
*3: Oil pressure is applied to 4th ªapplyº side in condition *2 above, and brake band contracts.
*4: A/T will not shift to 4th when overdrive control switch is set in ªOFFº position.
*5: Operates when overdrive control switch is ªOFFº.
j: Operates.
A: Operates when throttle opening is less than 3/16, activating engine brake.
B: Operates during ªprogressiveº 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-23

POWER TRANSMISSION=NJAT0013S02ªNº and ªPº PositionsNJAT0013S0201+ªNº position
Power from the input shaft is not transmitted to the output shaft because the clutches do not operate.
+ªPº position
Similar to the ªNº position, the clutches do not operate. The parking pawl engages with the parking gear
to mechanically hold the output shaft so that the power train is locked.
SAT991I
OVERALL SYSTEM
Shift Mechanism (Cont'd)
AT-24

ªD4º (OD) Position=NJAT0013S0206
+High clutch
+Brake band
+Forward clutch(Does not affect power
transmission)Input power is transmitted to front carrier through high clutch.
This front carrier turns around the sun gear which is fixed by brake band and makes
front internal gear (output) turn faster.
Engine brakeAt D
4position, there is no one-way clutch in the power transmission line and engine
brake can be obtained when decelerating.
SAT380J
OVERALL SYSTEM
Shift Mechanism (Cont'd)
AT-29

ªRº Position=NJAT0013S0207
+Reverse clutch
+Low and reverse brakeFront planetary carrier is stationary because of the operation of low and reverse
brake.
Input power is transmitted to front sun gear through reverse clutch, which drives front
internal gear in the opposite direction.
Engine brakeAs there is no one-way clutch in the power transmission line, engine brake can be
obtained when decelerating.
SAT381J
OVERALL SYSTEM
Shift Mechanism (Cont'd)
AT-30

TCM FUNCTION=NJAT0014S03The function of the TCM is to:
+Receive input signals sent from various switches and sensors.
+Determine required line pressure, shifting point, lock-up operation, and engine brake operation.
+Send required output signals to the respective solenoids.
INPUT/OUTPUT SIGNAL OF TCMNJAT0014S04
Sensors, switches and solenoid
valvesFunction
InputPNP switch Detects select lever position and sends a signal to TCM.
Throttle position sensor Detects throttle valve position and sends a signal to TCM.
Closed throttle position switch Detects throttle valve's fully-closed position and sends a signal to TCM.
Wide open throttle position switchDetects a throttle valve position of greater than 1/2 of full throttle and sends
a signal to TCM.
Engine speed signal From ECM.
A/T fluid temperature sensor Detects transmission fluid temperature and sends a signal to TCM.
Revolution sensor Detects output shaft rpm and sends a signal to TCM.
Vehicle speed sensorUsed as an auxiliary vehicle speed sensor. Sends a signal when revolution
sensor (installed on transmission) malfunctions.
Overdrive control switchSends a signal, which prohibits a shift to ªD
4º (overdrive) position, to the
TCM.
Stop lamp switch Releases lock-up system when depressing pedal in lock-up condition.
OutputShift solenoid valve A/BSelects shifting point suited to driving conditions in relation to a signal sent
from TCM.
Line pressure solenoid valveRegulates (or decreases) line pressure suited to driving conditions in rela-
tion to a signal sent from TCM.
Torque converter clutch solenoid
valveRegulates (or decreases) lock-up pressure suited to driving conditions in
relation to a signal sent from TCM.
Overrun clutch solenoid valveControls an ªengine brakeº effect suited to driving conditions in relation to a
signal sent from TCM.
O/D OFF indicator lamp Shows TCM faults, when A/T control components malfunction.
Control MechanismNJAT0015LINE PRESSURE CONTROLNJAT0015S01TCM has various line pressure control characteristics to match the
driving conditions.
An ON-OFF duty signal is sent to the line pressure solenoid valve
based on TCM characteristics.
Hydraulic pressure on the clutch and brake is electronically con-
trolled through the line pressure solenoid valve to accommodate
engine torque. This results in smooth shift operation.
OVERALL SYSTEM
Control System (Cont'd)
AT-32

SAT003J
Normal ControlNJAT0015S0101The line pressure to throttle opening characteristics is set for suit-
able clutch operation.
SAT004J
Back-up Control (Engine brake)NJAT0015S0102If the selector lever is shifted to ª2º position while driving in D4(OD)
or D
3, great driving force is applied to the clutch inside the trans-
mission. Clutch operating pressure (line pressure) must be
increased to deal with this driving force.
SAT005J
During Shift ChangeNJAT0015S0103The line pressure is temporarily reduced corresponding to a
change in engine torque when shifting gears (that is, when the shift
solenoid valve is switched for clutch operation) to reduce shifting
shock.
At Low Fluid TemperatureNJAT0015S0104+Fluid viscosity and frictional characteristics of the clutch facing
change with fluid temperature. Clutch engaging or band-con-
tacting pressure is compensated for, according to fluid
temperature, to stabilize shifting quality.
SAT006J
+The line pressure is reduced below 60ÉC (140ÉF) to prevent
shifting shock due to low viscosity of automatic transmission
fluid when temperature is low.
OVERALL SYSTEM
Control Mechanism (Cont'd)
AT-33

Pilot pressure generated by the operation of shift solenoid valves
A and B is applied to the end face of shift valves A and B.
The drawing above shows the operation of shift valve B. When the
shift solenoid valve is ªONº, pilot pressure applied to the end face
of the shift valve overcomes spring force, moving the valve upward.
LOCK-UP CONTROLNJAT0015S03The torque converter clutch piston in the torque converter is locked
to eliminate torque converter slip to increase power transmission
efficiency. The solenoid valve is controlled by an ON-OFF duty
signal sent from the TCM. The signal is converted to an oil pres-
sure signal which controls the torque converter clutch piston.
Conditions for Lock-up OperationNJAT0015S0301When vehicle is driven in 4th gear position, vehicle speed and
throttle opening are detected. If the detected values fall within the
lock-up zone memorized in the TCM, lock-up is performed.
Overdrive control switch ON OFF
Selector lever ªDº position
Gear position D
4D3
Vehicle speed sensor More than set value
Throttle position sensor Less than set opening
Closed throttle position switch OFF
A/T fluid temperature sensor More than 40ÉC (104ÉF)
SAT010J
Torque Converter Clutch Solenoid Valve ControlNJAT0015S0302The torque converter clutch solenoid valve is controlled by the
TCM. The plunger closes the drain circuit during the ªOFFº period,
and opens the circuit during the ªONº period. If the percentage of
OFF-time increases in one cycle, the pilot pressure drain time is
reduced and pilot pressure remains high.
The torque converter clutch piston is designed to slip to adjust the
ratio of ON-OFF, thereby reducing lock-up shock.
SAT011J
OFF-time INCREASING
¯
Amount of drain DECREASING
¯
Pilot pressure HIGH
¯
Lock-up RELEASING
OVERALL SYSTEM
Control Mechanism (Cont'd)
AT-35