engine NISSAN TEANA 2003 User Guide

A/T CONTROL SYSTEM
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Shift MechanismBCS000ZO
CONSTRUCTION
FUNCTION OF CLUTCH AND BRAKE
1. Torque converter 2. Oil pump 3. Input shaft
4. Brake band 5. Reverse clutch 6. High clutch
7. Front sun gear 8. Front pinion gear 9. Front internal gear
10. Front planetary carrier 11. Rear sun gear 12. Rear pinion gear
13. Rear internal gear 14. Rear planetary carrier 15. Forward clutch
16. Forward one-way clutch 17. Overrun clutch 18. Low one-way clutch
19. Low & reverse brake 20. Parking pawl 21. Parking gear
22. Output shaft 23. Idler gear 24. Output gear
SAT998I
Clutch and brake components Abbr. Function
5Reverse clutch R/C To transmit input power to front sun gear 7 .
6High clutch H/C To transmit input power to front planetary carrier 10 .
15Forward clutch F/C To connect front planetary carrier 10 with forward one-way clutch 16 .
17Overrun clutch O/C To connect front planetary carrier 10 with rear internal gear 13 .
4Brake band B/B To lock front sun gear 7 .
16Forward one-way clutch F/O.CWhen forward clutch 15 is engaged, to stop rear internal gear 13 from rotating
in opposite direction against engine revolution.
18Low one-way clutch L/O.CTo stop front planetary carrier 10 from rotating in opposite direction against
engine revolution.
19Low & reverse brake L & R/B To lock front planetary carrier 10 .

AT-18
A/T CONTROL SYSTEM

CLUTCH AND BAND CHART

*1: Oil pressure is applied to both 2nd “apply” side and 3rd “release” side of band servo piston. However, brake band does not con-
tract because oil pressure area on the “release” side is greater than that on the “apply” side.

*2: Oil pressure is applied to 4th “apply” side in condition *1 above, and brake band contracts.

: 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. Shift posi-
tionR/C
5H/C
6F/C
15O/C
17Band servo
F/O.C
16L/O.C
18L&R/B
19Lock-
upRemarks
2nd
apply3rd
release4th
apply
PPA R K
POSITION
RREVERSE
POSITION
NNEUTRAL
POSITION
1st D B B
D2nd A BAutomatic
shift
3rd A *1C C B1 ⇔ 2 ⇔ 3
⇔ 4
4th C *2C C
31st D B B
Automatic
shift
1 ⇔ 2 ⇔ 3 2nd A B
3rd A *1C C B
21stBB
Automatic
shift
1 ⇔ 2 ⇐ 3 2ndB
3rd *1C C B
11stBB
Locks (held
stationary)
in 1st speed
1 ⇐ 2 ⇐ 3 2ndB
3rd *1C C B

AT-20
A/T CONTROL SYSTEM

“11 ” Position

Forward one-way clutch

Forward clutch

Overrun clutch

Low & reverse brakeAs overrun clutch engages, rear internal gear is locked by the operation of low and
reverse brake.
This is different from that of D
1 , 31 and 21 .
Engine brake Overrun clutch always engages, therefore engine brake can be obtained when deceler-
ating.
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A/T CONTROL SYSTEM
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“D1 ”, “31 ” and “21 ” Positions

Forward one-way clutch

Forward clutch

Low one-way clutchRear internal gear is locked to rotate counterclockwise because of the functioning of
these three clutches.
Overrun clutch
engagement conditions
(Engine brake)D
1 and 31 : Throttle opening is less than 3/16
2
1 : Always engaged
At D
1 , 31 and 21 positions, engine brake is not activated due to free turning of low
one- way clutch.
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AT-24
A/T CONTROL SYSTEM

“D4 ” Position

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
4 position, there is no one-way clutch in the power transmission line and engine
brake can be obtained when decelerating.
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A/T CONTROL SYSTEM
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“R” Position

Reverse clutch

Low & 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.
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AT-26
A/T CONTROL SYSTEM

TCM FunctionBCS000ZP
The 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.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SWITCHES & SENSORS

TCM

ACTUATORS
PNP switch
Accelerator pedal position signal
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Turbine revolution sensor (power
train revolution sensor)
Vehicle speed signal
3rd position switch signal
Stop lamp switch signalShift control
Line pressure control
Lock-up control
Overrun clutch control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
control
CAN systemShift solenoid valve A
Shift solenoid valve B
Overrun clutch solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
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A/T CONTROL SYSTEM
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CAN CommunicationBCS000ZQ
SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-49,
"CAN System Specification Chart" .
Input/Output Signal of TCMBCS000ZR
*1: Spare for vehicle speed sensor·A/T (revolution sensor)
*2: Spare for accelerator pedal position signal
*3: If these input and output signals are different, the TCM triggers the fail-safe function.
*4: Used as a condition for starting self-diagnostics; if self-diagnostics are not started, it is judged that there is some kind of error.
*5: Input by CAN communications.
*6: Output by CAN communications.Control itemLine
pressure
controlVehicle
speed
controlShift
controlLock-up
controlEngine
brake
controlFail-safe
functionSelf-diag-
nostics
function
InputAccelerator pedal position signal
(*5)XXXXX(*3) XX
Vehicle speed sensor A/T
(Revolution sensor)XXXXX(*3) XX
Vehicle speed sensor MTR
(*1)XXXX X
Closed throttle position signal
(*5)(*2) X(*2) XXX(*4) X
Wide open throttle position signal
(*5)(*2) X (*2) X (*4) X
Turbine revolution sensor (Power
train revolution sensor)XX X XX
Engine speed signal X X X X
PNP switch XXXXX(*3) X(*4) X
Stop lamp switch signal
(*5)XX (*4) X
A/T fluid temperature sensors X X X X X X
3rd position switch signal
(*5)XXXX (*4) X
TCM power supply voltage signal X X X X
Out-
putShift solenoid valve A/B X (*3) X X
Line pressure solenoid X (*3) X X
Torque converter clutch solenoid
valveX(*3) XX
Overrun clutch solenoid valve X X (*3) X X
A/T CHECK indicator lamp
(*6)X

AT-28
A/T CONTROL SYSTEM

Line Pressure ControlBCS000ZS

TCM 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 controlled through the line pressure solenoid
valve to accommodate engine torque. This results in smooth shift operation.
NORMAL CONTROL
The characteristics of line pressure to throttle opening.
BACK-UP CONTROL (ENGINE BRAKE)
If the selector lever is shifted to “2” position while driving in D4 , D3
or 33 , great driving force is applied to the clutch inside the transmis-
sion. Clutch operating pressure (line pressure) must be increased to
deal with this driving force.
DURING SHIFT CHANGE
The 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.
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A/T CONTROL SYSTEM
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AT LOW FLUID TEMPERATURE

A/T fluid viscosity and frictional characteristics of the clutch facing change with A/T fluid temperature.
Clutch engaging or band-contacting pressure is compensated for, according to A/T fluid temperature, to
stabilize shifting quality.

The line pressure is reduced below 60°C (140°F) to prevent
shifting shock due to low viscosity of A/T fluid when temperature
is low.

Line pressure is increased to a maximum irrespective of the
throttle opening when A/T fluid temperature drops to −10°C
(14°F). This pressure rise is adopted to prevent a delay in clutch
and brake operation due to extreme drop of A/T fluid viscosity at
low temperature.
Shift ControlBCS000ZT
The shift is regulated entirely by electronic control to accommodate vehicle speed and varying engine opera-
tions. This is accomplished by electrical signals transmitted by the revolution sensor and the ECM (accelerator
pedal position sensor). This results in improved acceleration performance and fuel economy.
CONTROL OF SHIFT SOLENOID VALVES A AND B
The TCM activates shift solenoid valves A and B according to sig-
nals from the accelerator pedal position sensor and revolution sen-
sor to select the optimum gear position on the basis of the shift
schedule memorized in the TCM.
The shift solenoid valve performs simple ON-OFF operation. When
set to “ON”, the drain circuit closes and pilot pressure is applied to
the shift valve.
RELATION BETWEEN SHIFT SOLENOID VALVES A AND B AND GEAR POSITIONS
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SAT008J
Gear position 1 2 3 4
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)