STRUCTURE AND OPERATIONTM-229
< SYSTEM DESCRIPTION > [CVT: RE0F10E]
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TRANSAXLE : Component DescriptionINFOID:0000000009464201
FLUID COOLER & FLUID WARMER SYSTEM
Part name Function
Torque converter Increases engine torque and transmits it to the transaxle.
Oil pump Utilizes a vane-type oil pump that is driven by the engine through the oil pump drive chain in order to
increase efficiency of pump discharge volume in low-speed zone and optimize pump discharge volume
in high-speed zone. Discharged oil from oil pump is tr ansmitted to control valve. It is used as the oil of
primary and secondary pulley operation, the oil of clutch operation, and the lubricant for each part.
Forward clutch The forward clutch is wet and multiple plate type clutch that consists of clutch drum, piston, drive plate,
and driven plate. It is a clutch to move the vehicle forward by activating piston hydraulically, engaging
plates, and directly connecting sun gear and input shaft.
Reverse brake The reverse brake is a wet multiple-plate type brake that consists of transaxle case, piston, drive plate,
and driven plate. It is a brake to move the vehicle in reverse by activating piston hydraulically, engaging
plates, and fixing planetary gear.
Internal gear The internal gear is directly connected to forward clutch drum. It is a gear that moves the outer edge of
pinion planet of planet carrier. It transmits power to move the vehicle in reverse when the planet carrier
is fixed.
Planet carrier Composed of a carrier, pinion planet, and pinion shaft. This gear fixes and releases the planet carrier in
order to switch between forward and reverse driving.
Sun gear Sun gear is a set part with planet carrier and internal gear. It transmits transmitted force to primary fixed
sheave. It rotates in forward or reverse direction according to activation of either forward clutch or re-
verse brake.
Input shaft The input shaft is directly connected to forward clutch drum and transmits traction force from torque con-
verter. In shaft center, there are holes for hydraulic distribution to primary pulley and hydraulic distribution
for lockup ON/OFF.
Primary pulley It is composed of a pair of pulleys (the groove width is changed freely in the axial direction) and the chain belt. The groove width changes according to wrapping radius of steel belt and pulley from low status to
overdrive status continuously with non-step. It is controlled with the oil pressures of primary pulley and
secondary pulley.
Secondary pulley
Chain belt
Manual shaft When the manual shaft is in the P position, the parking rod that is linked to the manual shaft rotates the
parking pole. When the parking pole rotates, it engages with the parking gear, fixing the parking gear. As
a result, the secondary pulley that is integrated with the parking gear is fixed.
Parking rod
Parking pawl
Parking gear
Output gear
The deceleration gears are composed of 2 stages: primary deceleration (output gear, idler gear pair) and
secondary deceleration (reduction gear, final gear pair). All of these gears are helical gears.
Idler gear
Reduction gear
Differential
Torque converter regulator
valve Adjusts the feed pressure to the torque converter to the optimum pressure corresponding to the driving
condition.
Pressure regulator valve Adjusts the discharge pressure from the oil pump to the optimum pressure (line pressure) corresponding
to the driving condition.
Torque converter clutch
control valve Adjusts the torque converter engage and disengage pressures.
Manual valve Distributes the clutch operation pressure to each circuit according to the selector lever position.
Secondary reducing valve Reduces line pressure and adjusts secondary pressure.
Primary reducing valve Reduces line pressure and adjusts primary pressure.
Pilot valve A Reduces line pressure and adjusts pilot pressure to the solenoid valves listed below.
• Primary pressure solenoid valve
• Secondary pressure solenoid valve
• Select solenoid valve
• Line pressure solenoid valve
Pilot valve B Reduces pilot pressure and adjusts pilot pressure to the torque converter clutch solenoid valve.
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
SYSTEMTM-233
< SYSTEM DESCRIPTION > [CVT: RE0F10E]
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• CVT detects the vehicle driving status from switc hes, sensors and signals, and controls the vehicle so that
the optimum shift position and shift timing may always be achieved. It also controls the vehicle to reduce
shift and lockup shock, etc.
• Receives input signals from switches and sensors.
• Sends the output signal necessary for operation of so lenoid valves, and evaluates the line pressure, shift
timing, lockup operation, engine brake performance, etc.
• If a malfunction occurs on the electric system, activa te the fail-safe mode only to drive the vehicle.
LIST OF CONTROL ITEMS AND INPUT/OUTPUT
*: If these input/output signals show errors, TCM activates the fail-safe function.
CVT CONTROL SYSTEM : Fail-safeINFOID:0000000009464205
TCM has a fail-safe mode. The mode functions so that operation can be continued even if the signal circuit of
the main electronically controlled input/output parts is damaged.
If the vehicle shows following behaviors including “poor acceleration”, a malfunction of the applicable system
is detected by TCM and the vehicle may be in a fail-s afe mode. At this time, check the DTC code and perform
inspection and repair according to the malfunction diagnosis procedures.
Fail-safe function
Control Item Shift control Line pressure
control Select control Lock-up con-
trol Fail-safe func-
tion*
Input Engine torque signal
(CAN communication) ×××××
Engine speed signal
(CAN communication) ×××××
Accelerator pedal position signal
(CAN communication) ××××
Closed throttle position signal
(CAN communication) ×× ×
Stop lamp switch signal
(CAN communication) ××××
Primary pressure sensor ×
Secondary pressure sensor ×× ×
CVT fluid temperature sensor ×××××
Primary speed sensor ×××××
Output speed sensor ×× ××
Input speed sensor ×××××
Transmission range switch ×××××
Paddle shifter
(CAN communication) ×× ×
Output Line pressure solenoid valve
××× ×
Primary pressure solenoid valve ×× ×
Torque converter clutch solenoid
valve ××
Secondary pressure solenoid valve ×× ×
Select solenoid valve ×××
Shift position indicator
(CAN communication) ×
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
TM-236
< SYSTEM DESCRIPTION >[CVT: RE0F10E]
SYSTEM
CVT CONTROL SYSTEM : Protection Control
INFOID:0000000009464206
The TCM becomes the protection control status temporar ily to protect the safety when the safety of TCM and
transmission is lost. It automatically returns to the normal status if the safety is secured.
The TCM has the following protection control.
CONTROL FOR WHEEL SPIN
TORQUE IS REDUCED WHEN DRIVING WITH THE REVERSE GEAR
CONTROL WHEN FLUID TEMPERATURE IS HIGH
P2813 • Selector shock is large
•Start is slow
• Acceleration is slow
• Vehicle speed is not increased When a malfunction occurs on the low oil pressure side
• Selector shock is large When a malfunction occurs on the high oil pressure side
P2814 • Selector shock is large —
P2815 • Selector shock is large —
U0073 • Selector shock is large
•Start is slow
• Acceleration is slow
• Lock-up is not performed —
U0100 • Selector shock is large
•Start is slow
• Acceleration is slow
• Lock-up is not performed —
U0140 • Not changed from normal driving —
U0141 • Not changed from normal driving —
U0155 • Not changed from normal driving —
U0300 • Selector shock is large
•Start is slow
• Acceleration is slow
• Lock-up is not performed —
U1000 • Not changed from normal driving — U1117 • Not changed from normal driving — DTC Vehicle behavior Conditions of vehicle
Control
When a wheel spin is detected, the engine output and gear ratio are limited and the line pressure is increased.
Limits engine output when a wheel spin occurs in any of right and left drive wheels.
Vehicle behavior in
control If the accelerator is kept depressing during wheel spin, the engine revolution and vehicle speed are limited to
a certain degree.
Normal retu rn condi-
tion Wheel spin convergence returns the control to the normal control.
Control Engine output is controlled according to a vehicle speed while reversing the vehicle.
Vehicle behavior in
control Power performance may be lowered while reversing the vehicle.
Normal retu rn condi-
tion Torque returns to normal by positioning the selector lever in a range other than “R” position.
Control
When the CVT fluid temperature is high, the gear shift permission maximum revolution and the maximum
torque are reduced than usual to prevent increase of the oil temperature.
Vehicle behavior in
control Power performance may be lowered, compared to normal control.
Normal retu rn condi-
tion The control returns to the normal control when CVT fluid temperature is lowered.
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SYSTEMTM-237
< SYSTEM DESCRIPTION > [CVT: RE0F10E]
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REVERSE PROHIBIT CONTROL
LINE PRESSURE CONTROL
LINE PRESSURE CONTROL : System DescriptionINFOID:0000000009464207
SYSTEM DIAGRAM
DESCRIPTION
Highly accurate line pressure control (secondary pressure control) reduces friction for improvement of fuel
economy.
Normal Oil Pressure Control
Appropriate line pressure and secondary pressure suitable for driving condition are determined based on the
accelerator pedal position, engine speed, primary pulley (input) speed, secondary pulley (output) speed, vehi-
cle speed, input torque, stop lamp switch signal, transmission range switch signal, lock-up signal, power volt-
age, target shift ratio, oil temperature, oil pressure, and paddle shift (up/down) signal.
Secondary Pressure Feedback Control
In normal oil pressure control and oil pressure control in shifting, highly accurate secondary pressure is deter-
mined by detecting the secondary pressure using an oil pressure sensor and by feedback control.
SHIFT CONTROL
Control The reverse brake is controlled to avoid becoming engaged when the selector lever is set in “R” position while
driving in forward direction at more than the specified speed.
Vehicle behavior in
control If the selector lever is put at “R” position when driving with the forward gear, the gear becomes neutral, not
reverse.
Normal return condi-
tion The control returns to normal control when the vehicle is driven at low speeds. (The reverse brake becomes
engaged.)
JSDIA3716GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
TM-238
< SYSTEM DESCRIPTION >[CVT: RE0F10E]
SYSTEM
SHIFT CONTROL : System Description
INFOID:0000000009464208
SYSTEM DIAGRAM
DESCRIPTION
To select the gear ratio that can give the driving force to meet driver's intent or vehicle situation, the vehicle
driving condition such as vehicle speed or accelera tor pedal position is detected and the most appropriate
gear ratio is selected and the shifting method before reaching the speed is determined. The information is out-
put to the primary pressure solenoid valve and secondary pressure solenoid valve to control the line pressure
input/output to the pulley, to determine the pulley (mov able pulley) position and to control the gear position.
D Position
JSDIA3761GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
TM-244
< SYSTEM DESCRIPTION >[CVT: RE0F10E]
DIAGNOSIS SYSTEM (TCM)
• When the self-diagnosis result is acceptable at the 2nd
trip (conforming to driving condition B), DTC of the
1st trip is erased.
COUNTER SYSTEM LIST
DRIVING CONDITION
Driving condition A
Driving condition A is the driving condition that provides warm-up.
In specific, count-up is performed when all of the following conditions are satisfied.
• Engine speed is 400 rpm or more.
• After start of the engine, the water temperature increased by 20 °C (36 °F) or more.
• Water temperature was 70 °C (158 °F) or more.
• The ignition switch was changed from ON to OFF.
NOTE:
• If the same malfunction is detected regardless of the driving condition, reset the A counter.
• When the above is satisfied without detecting t he same malfunction, count up the A counter.
• When MIL goes off due to the malfunction and the A counter reaches 40, the DTC is erased.
Driving condition B
Driving condition B is the driving condition that performs all diagnoses once.
In specific, count-up is performed when all of the following conditions are satisfied.
• Engine speed is 400 rpm or more.
• Water temperature was 70 °C (158 °F) or more.
• In closed loop control, vehicle speed of 70 – 120 km/h (43 – 75 MPH) continued for 60 seconds or more.
• In closed loop control, vehicle speed of 30 – 60 km/h (19 – 37 MPH) continued for 10 seconds or more.
• In closed loop control, vehicle speed of 4 km/h (2 MPH) or less and idle determination ON continued for 12
seconds or more.
• After start of the engine, 22 minutes or more have passed.
• The condition that the vehicle speed is 10 km/h (6 MPH) or more continued for 10 seconds or more in total.
• The ignition switch was changed from ON to OFF.
NOTE:
• If the same malfunction is detected regardless of the driving condition, reset the B counter.
• When the above is satisfied without detecting t he same malfunction, count up the B counter.
• When the B counter reaches 3 wit hout malfunction, MIL goes off.
• When the B counter is counted once without detecting the same malfunction after TCM memorizes DTC of
the 1st trip, DTC of the 1st trip is erased.
Item Driving condition Trip
MIL (OFF) B 3
DTC (clear) A 40
DTC at 1st trip (clear) B 1
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DIAGNOSIS SYSTEM (TCM)TM-245
< SYSTEM DESCRIPTION > [CVT: RE0F10E]
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TIME CHART
CONSULT FunctionINFOID:0000000009464217
CAUTION:
After disconnecting the CONSULT vehicle interface (VI) from the data link connector, the ignition must
be cycled OFF → ON (for at least 5 seconds) → OFF. If this step is not performed, the BCM may not go
to ”sleep mode”, potentiall y causing a discharged battery and a no-start condition.
APPLICABLE ITEM
JSDIA1868GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
TM-246
< SYSTEM DESCRIPTION >[CVT: RE0F10E]
DIAGNOSIS SYSTEM (TCM)
SELF DIAGNOSTIC RESULTS
Display Item List
Refer to
TM-263, "DTC Index".
DTC at 1st trip and method to read DTC
• DTC (P0705, P0711, P0720, etc.) is specified by SAE J2012/ISO 15031-6.
• DTC and DTC at 1st trip are displayed on “Self Diagnostic results” of CONSULT.
When DTC is currently detected, “CRNT” is displayed. If “PAST” is displayed, it shows a malfunction
occurred in the past. The trip number of drive wit hout malfunction of concerned DTC can be confirmed with
“IGN counter” inside “FFD”.
• When the DTC at the 1st trip is detected, “1t” is displayed.
DTC deletion method
NOTE:
If the ignition switch is left ON after repair, turn O FF the ignition switch and wait for 10 seconds or more. Then,
turn the ignition ON again. (Engine stop)
1. Touch “TRANSMISSION” of CONSULT.
2. Touch “Self Diagnostic Result”.
3. Touch “Erase”. (DTC memorized in TCM is erased.)
IGN counter
The ignition counter is displayed in “FFD” and the number of times of satisfied “Driving condition A” is dis-
played after normal recovery of DTC. Refer to TM-243, "DIAGNOSIS DESCRIPTION : Counter System"
.
• If malfunction (DTC) is currently detected, “0” is displayed.
• After normal recovery, every time “Driving condition A” is satisfied, the display value increases from 1 → 2 →
3...38 → 39.
• When MIL turns OFF due to the malfunction and t he counter reaches 40, the DTC is erased.
NOTE:
The counter display of “40” cannot be checked.
DATA MONITOR
NOTE:
The following table includes information (items) inapplicable to this vehicle. For information (items) applicable
to this vehicle, refer to CONSULT display items.
× : Application : Optional selection
Conditions Function
Work Support The settings for ECU functions can be changed.
Self Diagnostic Results The ECU self diagnostic results are displayed.
Data Monitor The ECU input/output data is displayed in real time.
CAN Diagnosis Support Monitor The result of transmit/receive diagnosis of CAN communication is displayed.
Active Test The ECU activates outputs to test components.
ECU Identification The ECU part number is displayed.
CALIB DATA The calibration data status of TCM can be checked.
Monitored item (Unit) Monitor item selection
Remarks
ECU IN-
PUT SIG-
NALS MAIN SIG-
NALS
VSP SENSOR (km/h or mph) ×Displays the vehicle speed calculated from the CVT out-
put shaft speed.
ESTM VSP SIG (km/h or mph) ו Displays the vehi
cle speed signal (ABS) received
through CAN communication.
• Models with ABS are displayed.
INPUT SPEED SENSOR (rpm) ×Displays the input speed calculated from the pulse signal
of the input speed sensor.
PRI SPEED SEN (rpm) ×Displays the primary pulley speed calculated from the
pulse signal of the primary speed sensor.
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM