2007 NISSAN LATIO brake control system

CVT SYSTEM
CVT-27
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CVT
Revision: June 20062007 Versa
NOTE:
The gear ratio is set for every position separately.
“D” POSITION
Shifting over all the ranges of gear ratios from the lowest to the high-
est.
OVERDRIVE-OFF MODE
Use this position for the improved engine braking.
“L” POSITION
By limiting the gear range to the lowest position, the strong driving
force and the engine brake can be secured.
DOWNHILL ENGINE BRAKE CONTROL (AUTO ENGINE BRAKE CONTROL)
When downhill is detected with the accelerator pedal released, the engine brake will be strengthened up by
downshifting so as not to accelerate the vehicle more than necessary.
ACCELERATION CONTROL
According to vehicle speed and a change of accelerator pedal angle, driver's request for acceleration and driv-
ing scene are judged. This function assists improvement in acceleration feeling by making the engine speed
proportionate to the vehicle speed. And a shift map which can gain a larger driving force is available for com-
patibility of mileage with driveability.
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SCIA1955E

CVT-28
CVT SYSTEM
Revision: June 20062007 Versa
Lock-up and Select ControlUCS005XY

The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.

The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid
valve, which is controlled by a signal from TCM. The torque converter clutch control valve engages or
releases the torque converter clutch piston.

When shifting between “N” (“P”) ⇔ “D” (“R”), torque converter clutch solenoid controls engagement power
of forward clutch and reverse brake.

The lock-up applied gear range was expanded by locking up the
torque converter at a lower vehicle speed than conventional
CVT models.
TORQUE CONVERTER CLUTCH AND SELECT CONTROL VALVE CONTROL
Lock-up and Select Control System Diagram
Lock-up Released
In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.
Lock-up Applied
In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the torque
converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
Select Control
When shifting between “N” (“P”)⇔“D” (“R”), optimize the operating pressure on the basis of the throttle posi-
tion, the engine speed, and the secondary pulley (output) revolution speed to lessen the shift shock.
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SCIA2374E

CVT SYSTEM
CVT-29
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MA
B
CVT
Revision: June 20062007 Versa
Control ValveUCS005XZ
FUNCTION OF CONTROL VALVE
Name Function
Torque converter regulator valve Optimizes the supply pressure for the torque converter depending on driving conditions.
Pressure regulator valve Optimizes the discharge pressure from the oil pump depending on driving conditions.
TCC control valve

Activates or deactivate the lock-up.

Lock-up smoothly by opening lock-up operation excessively.
TCC solenoid valve Controls the TCC control valve or select control valve.
Shift control valveControls flow-in/out of line pressure from the primary pulley depending on the stroke dif-
ference between the stepping motor and the primary pulley.
Secondary valveControls the line pressure from the secondary pulley depending on operating condi-
tions.
Clutch regulator valve Adjusts the clutch operating pressure depending on operating conditions.
Secondary pressure solenoid valve Controls the secondary valve.
Line pressure solenoid valve Controls the line pressure control valve.
Step motor Controls the pulley ratio.
Manual valveTransmits the clutch operating pressure to each circuit in accordance with the selected
position.
Select control valve Engages forward clutch, reverse brake smoothly depending on select operation.
Select switch valveSwitches torque converter clutch solenoid valve control pressure use to torque con-
verter clutch control valve or select control valve.
Lock-up select solenoid valve Controls the select switch valve.

TROUBLE DIAGNOSIS
CVT-39
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CVT
Revision: June 20062007 Versa
44-3.Cruise testCVT-50
❏ CVT-186, "Vehicle Speed Does Not Change in “L” Position"
❏ CVT-187, "Vehicle Speed Does Not Change in overdrive-off mode"
❏ CVT-188, "Vehicle Speed Does Not Change in “D” Position"
❏ CVT-189, "Vehicle Does Not Decelerate by Engine Brake"
❏ perform self-diagnosis. Enter checks for detected items. CVT-60
❏ CVT-68, "DTC U1000 CAN COMMUNICATION LINE"
❏ CVT-72, "DTC P0615 START SIGNAL CIRCUIT"
❏ CVT-76, "DTC P0703 STOP LAMP SWITCH CIRCUIT"
❏ CVT-78, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ CVT-85, "DTC P0710 CVT FLUID TEMPERATURE SENSOR CIRCUIT"
❏ CVT-90, "DTC P0715 INPUT SPEED SENSOR CIRCUIT (PRI SPEED SENSOR)"
❏ CVT-95, "DTC P0720 VEHICLE SPEED SENSOR CVT (SECONDARY SPEED
SENSOR)"
❏ CVT-101, "DTC P0725 ENGINE SPEED SIGNAL"
❏ CVT-103, "DTC P0730 BELT DAMAGE"
❏ CVT-105, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ CVT-110, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ CVT-113, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ CVT-118, "DTC P0746 PRESSURE CONTROL SOLENOID A PERFORMANCE
(LINE PRESSURE SOLENOID VALVE)"
❏ CVT-121, "DTC P0776 PRESSURE CONTROL SOLENOID B PERFORMANCE
(SEC PRESSURE SOLENOID VALVE)"
❏ CVT-124, "DTC P0778 PRESSURE CONTROL SOLENOID B ELECTRICAL (SEC
PRESSURE SOLENOID VALVE)"
❏ CVT-129, "DTC P0840 TRANSMISSION FLUID PRESSURE SENSOR A CIRCUIT
(SEC PRESSURE SENSOR)"
❏ CVT-134, "DTC P0841 PRESSURE SENSOR FUNCTION"
❏ CVT-137, "DTC P0845 TRANSMISSION FLUID PRESSURE SENSOR B CIRCUIT
(PRI PRESSURE SENSOR)"
❏ CVT-142, "DTC P0868 SECONDARY PRESSURE DOWN"
❏ CVT-145, "DTC P1701 TRANSMISSION CONTROL MODULE (POWER SUPPLY)"
❏ CVT-150, "DTC P1705 THROTTLE POSITION SENSOR"
❏ CVT-152, "DTC P1722 ESTM VEHICLE SPEED SIGNAL"
❏ CVT-154, "DTC P1723 CVT SPEED SENSOR FUNCTION"
❏ CVT-156, "DTC P1726 ELECTRIC THROTTLE CONTROL SYSTEM"
❏ CVT-158, "DTC P1740 LOCK-UP SELECT SOLENOID VALVE CIRCUIT"
❏ CVT-164, "DTC P1777 STEP MOTOR - CIRCUIT"
❏ CVT-168, "DTC P1778 STEP MOTOR - FUNCTION"
5❏ Inspect each system for items found to be NG in the self-diagnosis and repair or replace the malfunctioning parts.
6❏ Perform all road tests and enter the checks again for the required items.CVT-46
7❏ For any remaining NG items, perform the “diagnosis procedure” and repair or replace the malfunctioning parts.
8❏ Erase the results of the self-diagnosis from the TCM.CVT-32
,
CVT-32

CVT-192
SHIFT CONTROL SYSTEM
Revision: June 20062007 Versa
CONTROL CABLE COMPONENTS
Refer to the figure below for control cable removal and installation procedure.
REMOVAL
CAUTION:
Make sure that parking brake is applied before removal and installation.
1. Place the selector lever in the “N” position.
2. Remove the center console assembly. Refer to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
3. Disconnect the CVT device harness connector (1).
4. Remove the key interlock cable from the control device assem-
bly. Refer to CVT-202, "
Removal and Installation" .
5. Remove the bolts (A) from the control device assembly (1).
6. Remove exhaust front tube, center muffler and heat plates.
Refer to EM-21, "
EXHAUST MANIFOLD" .
1. Selector lever knob 2. Control device assembly 3. Lock plate
4. Bracket 5. Control cable 6. Bracket
7. Lock plate 8. Bracket 9. Transaxle assembly
A. Floor
WCIA0639E
SCIA6965E
WCIA0609E

SHIFT CONTROL SYSTEM
CVT-195
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CVT
Revision: June 20062007 Versa
Selector Lever Knob Removal and InstallationUCS006XQ
REMOVAL
CAUTION:
Make sure that parking brake is applied before removal/installation.
1. Set selector lever knob (1) in “N” position.
2. Slide knob cover (2) downward.
3. Pull out lock pin (3) from selector lever knob (1).
4. Remove selector lever knob (1) and knob cover (2) as a set from
selector lever.
CAUTION:
Do not push selector button.
INSTALLATION
1. Insert lock pin (1) to selector lever knob (2).
2. Install knob cover (3) to selector lever knob (2).
3. Set selector lever in “N” position.
4. Install selector lever knob over selector lever until a click is felt.
CAUTION:

Do not tilt selector lever knob when installing. Install it
straight, and do not tap or apply any shock to install it.

Do not push selector button.
Adjustment of CVT PositionUCS0064J
CAUTION:
Make sure that parking brake is applied before adjustment.
1. Loosen the control cable nut (A) and place the manual lever (1)
in “P” position.
2. Place selector lever in “P” position.
3. Push the control cable (2) in with a load of 9.8 N (approximately
1 kg, 2.2 lb). Release the control cable and temporarily tighten
the control cable nut.
NOTE:
Do not move the manual lever. Make sure the manual lever
stays in the “P” position.
4. Tighten the control cable nut.
CAUTION:
Secure the manual lever when tightening nut.
5. Check the operation of the CVT. Refer to CVT-196, "
Checking of CVT Position" .
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Control cable nut: Refer to CVT-192, "CON-
TROL CABLE COMPO-
NENTS" .
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CVT-196
SHIFT CONTROL SYSTEM
Revision: June 20062007 Versa
Checking of CVT PositionUCS0064K
1. Place selector lever in “P” position, and turn ignition switch ON. (Do not start engine.)
2. Make sure selector lever can be shifted to other than “P” position when brake pedal is depressed. Also
make sure selector lever can be shifted from “P” position only when brake pedal is depressed.
3. Move the selector lever and check for excessive effort, sticking, noise or rattle.
4. Confirm the selector lever stops at each position with the feel of engagement when it is moved through all
the positions. Check that the actual position of the selector lever matches the position shown by the shift
position indicator and the manual lever on the transaxle.
5. The method of operating the selector lever to individual posi-
tions correctly should be as shown.

(A): Press selector button to operate selector lever, while
depressing the brake pedal.

(B): Press selector button to operate selector lever.

(C): Selector lever can be operated without pressing selector
button.
6. Confirm the back-up lamps illuminate only when selector lever is
placed in the “R” position. Confirm the back-up lamps do not illu-
minate when the selector lever is pushed toward the “R” position
side with the gear position remained in the “P” or “N” position.
7. Confirm the engine can only be started with the selector lever in the “P” and “N” positions.
8. Make sure transaxle is locked completely in “P” position.
WCIA0620E

CVT SHIFT LOCK SYSTEM
CVT-197
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B
CVT
Revision: June 20062007 Versa
CVT SHIFT LOCK SYSTEMPFP:00000
DescriptionUCS0064L

The mechanical key interlock mechanism also operates as a shift lock:
With the ignition switch turned to ON, selector lever cannot be shifted from “P” position to any other posi-
tion unless brake pedal is depressed.
With the key removed, selector lever cannot be shifted from “P” position to any other position.
The key cannot be removed unless selector lever is placed in “P” position.

The shift lock and key interlock mechanisms are controlled by the ON-OFF operation of the shift lock sole-
noid and by the operation of the rotator and slider located inside key cylinder, respectively.
Shift Lock System Electrical Parts LocationUCS0064M
1. Key interlock cable 2. Key cylinder 3. Stop lamp switch
4. Brake pedal 5. Shift lock release button 6. Key interlock cable
7. Shift lock solenoid 8. Park position switch
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