NISSAN LATIO 2009 Service Service Manual

SAT015J
SCIA7172E

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Control Valve
INFOID:0000000004305307
FUNCTION OF CONTROL VALVES
Centrifugal Cancel Mechanism INFOID:0000000004305308
FUNCTION The centrifugal cancel mechanism is a mechanism to c ancel the centrifugal hydraulic pressure instead of the
conventional check balls. It cancels the centrifugal hy draulic 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
plug Regulates 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 D4. (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 12 to 1 1.
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 sleeve Activates 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.

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ON BOARD DIAGNOSTIC (OBD) SYSTEM
Introduction INFOID:0000000004305309
A/T system has two self-diagnostic systems.
The first is emission-related on boar d diagnostic system (OBD-II) performed by the TCM in combination with
the ECM. The malfunction is indicated by the MIL (malf unction indicator lamp) and is stored as a DTC in the
ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the OD OFF indicator lamp. The malfunction is
stored in the TCM memory. The detected items are ov erlapped with OBD-II self-diagnostic items. For detail,
refer to AT-79, " CONSULT-III Function (TRANSMISSION) " .
OBD-II Function for A/T System INFOID:0000000004305310
The ECM provides emission-related on board diagnostic (O BD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-rela ted parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-re lated part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indica tor lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-II INFOID:0000000004305311
ONE TRIP DETECTION LOGIC If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st trip
If the same malfunction as that experienced during the fi rst test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd trip
The “trip” in the “One or Two Trip Detection Logic” m eans a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC) INFOID:0000000004305312
HOW TO READ DTC AND 1ST TRIP DTC DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-III or GST) CONSULT-III or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
• 1st trip DTC No. is the same as DTC No.
• Output of the diagnostic troubl e code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring or
occurred in the past and returned to normal.
CONSULT-III can identify them as shown below, therefore, CONS ULT-III (if available) is recom-
mended.
DTC or 1st trip DTC of a malfunction is displayed in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with
CONSULT-III. Time data indicates how many times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected curr ently, the time data will be “0”.
If a 1st trip DTC is stored in the ECM, the time data will be “1t”.
Freeze Frame Data and 1st Trip Freeze Frame Data The ECM has a memory function, which stores the driv ing condition such as fuel system status, calculated
load value, engine coolant temperature, short term f uel trim, long term fuel trim, engine speed and vehicle
speed at the moment the ECM detects a malfunction.

CONSULT-III Function " (HR16DE),
EC-604, " CONSULT-III Function (ENGINE) " (MR
Type 1) or EC-1116, " CONSULT-III F
unction (ENGINE) " (MR Type 2).
Only one set of freeze frame data (either 1st trip freez e frame data of freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
Both 1st trip freeze frame data and freeze frame dat a (along with the DTC) are cleared when the ECM mem-
ory is erased.
HOW TO ERASE DTC
The diagnostic trouble code can be erased by CONSULT- III, GST or ECM DIAGNOSTIC TEST MODE as
described following.
• If the battery cable is disconnected, the diagnosti c trouble code will be cleared within 24 hours.
• When you erase the DTC, using CONSULT-III or GS T is easier and quicker than switching the mode
selector on the ECM.
The following emission-related diagnostic information is cleared from the ECM memory when erasing DTC
related to OBD-II. For details, refer to EC-90, " Diagnosis Description " (HR16DE),
EC-542, " Emission-related
Diagnostic Information " (MR Type 1) or
EC-1052, " Emission-related Diagnostic Information " (MR Type 2).
• Diagnostic trouble codes (DTC)
• 1st trip diagnostic trou ble codes (1st trip DTC)
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
• Test values
HOW TO ERASE DTC (WITH CONSULT-III)
• If a DTC is displayed for both ECM and TCM, it is necessary to be erased for both ECM and TCM.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Turn CONSULT-III “ON” and touch “TRANSMISSION”.
3. Touch “SELF-DIAG RESULTS”.
4. Touch “ERASE”. (The DTC in the TCM will be erased.) Then touch “BACK” twice.
5. Touch “ENGINE”.
6. Touch “SELF-DIAG RESULTS”.
7. Touch “ERASE”. (The DTC in the ECM will be erased.)
HOW TO ERASE DTC (WITH GST)
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform “TCM SELF-DIAGNOSTIC PROCEDURE (No Tools)”. Refer to AT-83, " Diagnosis Procedure
without CONSULT-III " . (The engine warm-up step can be skipped when performing the diagnosis only to
erase the DTC.)
3. Select Mode 4 with Generic Scan Tool (GST). For details, refer to EC-110, " Diagnosis Tool Function "
(HR16DE),
EC-612, " Generic Scan Tool (GST) Function " (MR Type 1) or
EC-1124, " Generic Scan Tool
(GST) Function " (MR Type 2).
HOW TO ERASE DTC (NO TOOLS)
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0306
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data

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The OD OFF indicator lamp is located on the combination meter.
1. If the ignition switch stays ON after repair work, be su re to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Perform “TCM SELF-DIAGNOSTIC PR OCEDURE (No Tools)”. Refer to AT-83, " Diagnosis Procedure
without CONSULT-III " . (The engine warm-up step can be ski
pped when performing the diagnosis only to
erase the DTC.)
3. Perform “OBD-II SELF-DIAGNOSTIC PROCEDURE (No tools)”. Refer to EC-90, " Diagnosis Description "
(HR16DE),
EC-542, " Emission-related Diagnostic Information " (MR Type 1) or
EC-1052, " Emission-
related Diagnostic Information " (MR Type 2).
Malfunction Indicator Lamp (MIL) INFOID:0000000004305313
DESCRIPTION The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON with- out the engine running. This is a bulb check.
• If the MIL does not light up, refer to DI-20, " Schematic " ,
EC- 447, " Wiring Diagram " (HR16DE),
EC-1010, " Wiring Diagram "
(MR Type 1) or
EC-1532, " Wiring Diagram " (MR Type 2).
2. When the engine is start ed, the MIL should go off.
• If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.

.
Fail-Safe INFOID:0000000004305315
The TCM has an electronic Fail-safe mode. This allows t he vehicle to be driven even if a major electrical input/
output device circuit is damaged.
Under Fail-Safe, the vehicle always runs in third gear, even with a shift lever position of “1”, “2” or “D”. The cus-
tomer may complain of sluggish or poor acceleration.
Always follow the “ AT-43, " How to Perform Trouble Diagnosis for Quick and Accurate Repair " ”.
The SELF-DIAGNOSIS results will be as follows:
• The first SELF-DIAGNOSIS will indicate damage to t he vehicle speed sensor or the revolution sensor.
• During the next SELF-DIAGNOSIS, performed after checking the sensor, no damages will be indicated.
FAIL-SAFE FUNCTION
The following fail-safe functions allow vehicles to be driven even when sensor, switch or solenoid malfunction
occurs.
Vehicle Speed Sensor·A/T (Revolution Sensor)
Vehicle speed sensor·MTR signal is input from combination meter.
Accelerator Pedal Position Signal and Throttle Position Signal
TCM controls the throttle opening angle to a predetermi ned fixed position to enable driving if a malfunctioning
signal is input to TCM.
PNP Switch
When the multiple PNP switch signals are input to TCM, the priority of selector lever position becomes “D”,
“N”, “R”, “2” and “1” in order by internal TCM determination.
The use of 4th gear is inhibited unt il normal operation resumes. Because t he hydraulic circuit of the control
valve is switched by manual valve according to the sele ctor lever position, however, actual operating condition
of vehicle becomes as follows.
Shift Solenoid Valve A and B
If non-standard solenoid signal is sent to TCM, use of certain gears is limited. Refer to chart shown below.
Priority Detected items
1 CAN communication line
2 Except above Actual lever position PNP switch input signal Running status
“P” “P” position and other position signals P
“R” “R” position and other position signals R
“N” “N” position and other position signals N
“D” “D” position and other position signals D 1
⇔ D2 ⇔ D3 ⇔ D4
“2” “2” position and other position signals (Except “1” position) 2
1 ⇔ 22 ⇔ 23
“2” position and “1” position signals 2 1 ⇔ 22
“1” “1” position and other position signals (Except “2” position) 1
1
⇔ 12 ⇔ 13
“1” position and “2” position signals 1 1 ⇔ 12

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z
: Solenoid ON
× : Solenoid OFF
–: Non-standard condition
Line Pressure Solenoid Valve If non-standard solenoid signal is sent to TCM, line pre ssure 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 conv erter clutch solenoid valve is turned OFF to release
lock-up.
Overrun Clutch Solenoid Valve If non-standard solenoid signal is sent to TCM, overr un 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 Repair INFOID:0000000004305316
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 wit h 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. T he 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 t hat occurs intermittently rather than continuously. Most
intermittent malfunctions are caused by poor electric c onnections or improper wiring. In this case, careful
checking of suspected circuits may hel p prevent the replacement of good parts.
Shift position
Normal
Malfunction in solenoid
valve A Malfunction in solenoid
valve B Malfunction in solenoid
valves A and B
A B Gear A B Gear A B Gear A B Gear
“D” position z z
1st –z→×
3rd z
→× –
3rd – –
3rd
×
z2nd – z→× × – – –
× × 3rd – x ×– – –
z ×4th – x z→× – – –
“2” position z z
1st –z→× z→× – – –
× z2nd – z→× × – – –
× × 3rd – x ×– – –
“1” position z z
1st –z→× z→× – – –
× z2nd – z→× × – – –
× × 3rd – x ×– – –

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DIAGNOSTIC WORKSHEET
Information from Customer
KEY POINTS
• WHAT ..... Vehicle & A/T model
• WHEN ..... Date, Frequencies
• WHERE ..... Road conditions
• HOW ..... Operating conditions, Symptoms
*1 "Information from customer" *2 "Diagnostic Worksheet Chart" *3
AT-42*4
AT-51 *5
AT-51 ,
AT-51 *6
AT-55 *7
AT-79 *8
AT-39 *9
AT-42 *10
AT-101 *11
AT-168 *12
AT-178 *13
AT-65 *14
AT-39 *15
AT-88 *16
AT-168 *17
EC-90 (HR16DE),
EC-542 (MR
Type 1) or EC-1052 (MR Type 2)