2008 NISSAN TIIDA Brake System

A/T CONTROL SYSTEM
AT-33
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
OVERRUN CLUTCH OPERATING CONDITIONS
OVERRUN CLUTCH SOLENOID VALVE CONTROL
The overrun clutch solenoid valve is operated by an ON-OFF signal
transmitted by the TCM to provide overrun clutch control (engine
brake control).
When this solenoid valve is “ON”, the pilot pressure drain port
closes. When it is “OFF”, the drain port opens.
During the solenoid valve “ON” pilot pressure is applied to the end
face of the overrun clutch control valve.
OVERRUN CLUTCH CONTROL VALVE OPERATION
When the solenoid valve is “ON”, pilot pressure is applied to the
overrun clutch control valve. This pushes up the overrun clutch con-
trol valve. The line pressure is then shut off so that the clutch does
not engage. Only in “1” position, however, 1 range pressure is
applied to overrun clutch control valve, resulting in valve moving
downward and clutch engaged.
When the solenoid valve is “OFF”, pilot pressure is not generated. At
this point, the overrun clutch control valve moves downward by
spring force. As a result, overrun clutch operation pressure is pro-
vided by the overrun clutch reducing valve. At overrun clutch reduc-
ing valve in “D” position, the hydraulic pressure is reduced to a level
that balances the spring force. This is sent to overrun clutch control
valve and becomes the operating pressure of overrun clutch which is
engaged at all times. In “2” position and “1” position, overrun clutch
reducing valve is pushed down by 2 range pressure. Line pressure is
directly sent to overrun clutch control valve and becomes the operat-
ing pressure of overrun clutch which is engaged at all times.
SCIA7186E
SAT015J
SCIA7172E

AT-34
< SERVICE INFORMATION >
A/T CONTROL SYSTEM
Control Valve
INFOID:0000000001703170
FUNCTION OF CONTROL VALVES
Centrifugal Cancel MechanismINFOID:0000000001703171
FUNCTION
The centrifugal cancel mechanism is a mechanism to cancel the centrifugal hydraulic pressure instead of the
conventional check balls. It cancels the centrifugal hydraulic pressure which is generated as high clutch drum
rotates, and it allows for preventing high clutch from dragging and for providing stable high clutch piston press-
ing force in all revolution speeds.
STRUCTURE/OPERATION
Valve name Function
Pressure regulator valve, plug and sleeve
plugRegulates oil discharged from the oil pump to provide optimum line pressure for all driving
conditions.
Pressure modifier valve and sleeve Used as a signal supplementary valve to the pressure regulator valve. Regulates pres-
sure-modifier pressure (signal pressure) which controls optimum line pressure for all driv-
ing conditions.
Pilot valve Regulates line pressure to maintain a constant pilot pressure level which controls lock-up
mechanism, overrun clutch, shift timing.
Accumulator control valve Regulates accumulator back-pressure to pressure suited to driving conditions.
Manual valve Directs line pressure to oil circuits corresponding to select positions.
Hydraulic pressure drains when the shift lever is in Neutral.
Shift valve A Simultaneously switches three oil circuits using output pressure of shift solenoid valve A
to meet driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve B.
Shift valve B Simultaneously switches two oil circuits using output pressure of shift solenoid valve B in
relation to driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and upshifting (1st → 2nd → 3rd → 4th gears/4th → 3rd
→ 2nd → 1st gears) in combination with shift valve A.
Overrun clutch control valve Switches hydraulic circuits to prevent engagement of the overrun clutch simultaneously
with application of the brake band in D
4. (Interlocking occurs if the overrun clutch engages
during D
4.)
1st reducing valve Reduces low & reverse brake pressure to dampen engine-brake shock when downshift-
ing from the 1st position 1
2 to 11.
Overrun clutch reducing valve Reduces oil pressure directed to the overrun clutch and prevents engine-brake shock.
In the 1st and 2nd positions, line pressure acts on the overrun clutch reducing valve to
increase the pressure-regulating point, with resultant engine brake capability.
Torque converter relief valve Prevents an excessive rise in torque converter pressure.
Torque converter clutch control valve, plug
and sleeveActivates or inactivates the lock-up function.
Also provides smooth lock-up through transient application and release of the lock-up
system.
1-2 accumulator valve and piston Lessens the shock find when the 2nd gear band servo contracts, and provides smooth
shifting.
3-2 timing valve Switches the pace that oil pressure is released depending on vehicle speed; maximizes
the high clutch release timing, and allows for soft downshifting.
Shuttle valve Determines if the overrun clutch solenoid valve should control the 3-2 timing valve or the
overrun clutch control valve and switches between the two.
Cooler check valve At low speeds and with a small load when a little heat is generated, saves the volume of
cooler flow, and stores the oil pressure for lock-up.

AT-40
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
●: Solenoid ON
×: Solenoid OFF
–: Non-standard condition
Line Pressure Solenoid Valve
If non-standard solenoid signal is sent to TCM, line pressure solenoid valve is turned OFF to achieve maxi-
mum oil pressure.
Torque Converter Clutch Solenoid Valve
If non-standard solenoid signal is sent to TCM, torque converter clutch solenoid valve is turned OFF to release
lock-up.
Overrun Clutch Solenoid Valve
If non-standard solenoid signal is sent to TCM, overrun clutch solenoid valve is turned OFF to engage overrun
clutch. This will result in more effective engine brake during deceleration.
How to Perform Trouble Diagnosis for Quick and Accurate RepairINFOID:0000000001703179
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, accelera-
tor pedal position sensor or PNP switch and provides shift control or
lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a malfunction that occurs intermittently rather than continuously. Most
intermittent malfunctions are caused by poor electric connections or improper wiring. In this case, careful
checking of suspected circuits may help prevent the replacement of good parts.
Shift positionNormalMalfunction in solenoid
valve AMalfunction in solenoid
valve BMalfunction in solenoid
valves A and B
A B Gear A B Gear A B Gear A B Gear
“D” position●●1st –●→×
3rd ●→×–
3rd ––
3rd ×●2nd –●→× ×–––
××3rd – x×–––
●×4th – x●→×–––
“2” position●●1st –●→×●→×–––
×●2nd –●→× ×–––
××3rd – x×–––
“1” position●●1st –●→×●→×–––
×●2nd –●→× ×–––
××3rd – x×–––
SAT631IA

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-189
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
NG >> GO TO 5.
5.DETECT MALFUNCTIONING ITEM
1. Remove control valve assembly. Refer to AT-216, "
Control Valve Assembly and Accumulators" .
2. Check the following items:
- Shift valve A
- Overrun clutch control valve
- Shift solenoid valve A
- Overrun clutch solenoid valve
- Pilot valve
- Pilot filter
3. Disassemble A/T. Refer to AT-240, "
Disassembly" .
4. Check the following items:
- Servo piston assembly
- Brake band
- Torque converter. Refer to AT-240, "
Disassembly" .
- Oil pump assembly. Refer to AT-260, "
Oil Pump" .
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
6.DETECT MALFUNCTIONING ITEM
1. Remove control valve assembly. Refer to AT-216, "
Control Valve Assembly and Accumulators" .
2. Check the following items:
- Shift valve A
- Overrun clutch control valve
- Shift solenoid valve A
- Pilot valve
- Pilot filter
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-55, "
Cruise Test - Part 1" and AT-58, "Cruise Test - Part 2" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.CHECK TCM
1. Check TCM input/output signals. Refer to AT-71, "
TCM Terminal and Reference Value" .
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
A/T Does Not Perform Lock-upINFOID:0000000001703346
SYMPTOM:
A/T does not perform lock-up at the specified speed on “Cruise Test — Part 1”.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT-73, "
CONSULT-III Function (A/T)" or AT-78, "Diagnosis Procedure without
CONSULT-III" .
Is any malfunction detected by self-diagnostic results?
YES >> Check the malfunctioning system. Refer to AT-73, "CONSULT-III Function (A/T)" or AT-78, "Diag-
nosis Procedure without CONSULT-III" .

AT-204
< SERVICE INFORMATION >
SHIFT CONTROL SYSTEM
REMOVAL
CAUTION:
Make sure that parking brake is applied before removal/installation.
1. Place the selector lever in the “N” position.
2. Remove the center console assembly. Refer to IP-10
.
3. Disconnect the A/T device harness connector (1).
4. Remove the key interlock cable from the control device assem-
bly. Refer to AT-213, "
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
.
1. Selector lever knob 2. Control device assembly 3. Lock plate
4. Floor panel 5. Control cable 6. Bracket
7. Lock plate 8. Lock nut 9. A/T assembly
10. Bracket 11. Bracket
WCIA0640E
SCIA6965E
WCIA0609E

AT-206
< SERVICE INFORMATION >
SHIFT CONTROL SYSTEM
• When installing the control cable (1) to the control device assembly
(2), make sure that the control cable (1) is fully pressed in with the
ribbed surface (A) facing downward from the vehicle.
: Vehicle front
• After installation is completed, adjust and check the A/T position.
Refer to AT-207, "
Adjustment of A/T Position" and AT-207, "Check-
ing of A/T Position".
Control Device Disassembly and AssemblyINFOID:0000000001703357
DISASSEMBLY
NOTE:
Refer to AT-203, "
Control Device Removal and Installation" to disassemble.
1. Remove selector lever knob from control device assembly. Refer to AT-206, "
Selector Lever Knob
Removal and Installation".
2. Remove position lamp from position indicator plate (1).
3. Insert a flat-bladed screwdriver to (A) (at 4 locations) as shown,
and bend each hook slightly to raise position indicator plate (1)
and remove from control device assembly (2).
4. Remove bracket from control device assembly (2).
5. Remove A/T device harness connector from control device
assembly (2).
6. Release tabs (A) on shift lock solenoid and park position switch
assembly from hooks (B) on control device assembly to shift
lock solenoid and park position switch assembly.
ASSEMBLY
Assemble in the reverse order of disassembly.
Selector Lever Knob Removal and InstallationINFOID:0000000001703358
REMOVAL
CAUTION:
Make sure that parking brake is applied before removal/installation.
SCIA6253E
SCIA6969E
SCIA6977E

SHIFT CONTROL SYSTEM
AT-207
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
1. Place the 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. Place the 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 A/T PositionINFOID:0000000001703359
Move selector lever from “P” position to “1” position. You should be able to feel the detents in each position. If
the detents cannot be felt or if the position indicator is improperly aligned, the control cable needs adjustment.
CAUTION:
Make sure that parking brake is applied before adjustment.
1. Remove the air duct assembly. Refer to EM-16
.
2. Remove the control cable nut (A) and control cable (1) and
place the manual lever (2) in the "P' position.
3. Place selector lever in “P” position.
4. Hold control cable (1) at the end and pull it with a force of 9.8 N
(approximately 1 kg, 2.2 lb). Release the control cable and tem-
porarily tighten control cable nut (A).
5. Tighten control cable nut (A) to the specified torque.
CAUTION:
Secure manual lever when tightening nut.
6. Move selector lever from “P” to “1” position again. Make sure that selector lever moves smoothly.
7. Check A/T position. Refer to AT-207, "
Checking of A/T Position".
8. Install air duct assembly. Refer to EM-16
.
Checking of A/T PositionINFOID:0000000001703360
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 selector lever and check for excessive effort, sticking, noise or rattle.
4. Confirm selector lever stops at each position with the feel of engagement when it is moved through all the
positions. Check whether or not the actual position selector lever is in matches the position shown by the
shift position indicator and the transaxle.
SCIA6971E
SCIA6972E
Control cable nut : Refer to AT-203, "Control De-
vice Removal and Installation".WCIA0635E

AT-208
< SERVICE INFORMATION >
SHIFT CONTROL SYSTEM
5. The method of operating selector lever to individual positions
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 back-up lamps illuminate only when selector lever is
placed in “R” position. Confirm back-up lamps do not illuminate
when selector lever is in “P” or “N” position even if it is pushed
toward “R” position without pressing selector button.
7. Confirm engine can only be started with selector lever in “P” and
“N” positions.
8. Make sure A/T is locked completely in “P” position.
WCIA0636E