NISSAN LATIO 2007 Service Repair Manual

CVT-164
DTC P1777 STEP MOTOR - CIRCUIT
Revision: June 20062007 Versa
DTC P1777 STEP MOTOR - CIRCUITPFP:31020
DescriptionUCS0063I

The step motor is included in the control valve assembly.

The step motor changes the step with turning 4 coils ON/OFF according to the signal from TCM. As a
result, the flow of line pressure to primary pulley is changed and pulley ratio is controlled
CONSULT-II Reference ValueUCS0063J
Remarks: Specification data are reference values.
On Board Diagnosis LogicUCS0063K

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1777 STEP MOTR CIRC” with CONSULT-II is detected under the following
conditions.
–When operating step motor ON and OFF, there is no proper change in the voltage of TCM terminal which
corresponds to it.
Possible CauseUCS0063L

Step motor

Harness or connectors
(Step motor circuit is open or shorted.)
DTC Confirmation ProcedureUCS0063M
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, touch “ERASE” on “SELF-DIAG RESULTS” and then perform the following procedure to con-
firm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
2. Drive vehicle for at least 5 consecutive seconds.
3. If DTC is detected, go to CVT-166, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II”.
Item name Condition Display value (Approx.)
STM STEP
During driving−20 step - 180 step
SMCOIL A
Changes ON⇔OFF. SMCOIL B
SMCOIL C
SMCOIL D
BCIA0031E

DTC P1777 STEP MOTOR - CIRCUIT
CVT-165
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CVT
Revision: June 20062007 Versa
Wiring Diagram — CVT — STMUCS0063N
BCWA0681E

CVT-166
DTC P1777 STEP MOTOR - CIRCUIT
Revision: June 20062007 Versa
TCM terminals data are reference values, measured between each terminal and ground.
Diagnostic ProcedureUCS0063O
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “TRANSMISSION” with CONSULT-II.
3. Start vehicle and read out the value of “STM STEP”, “SMCOIL
A”, “SMCOIL B”, “SMCOIL C”, and “SMCOIL D”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK HARNESS BETWEEN TCM AND STEP MOTOR
1. Turn ignition switch OFF.
2. Disconnect CVT unit connector and TCM connector.
3. Check continuity between TCM connector terminals and CVT
unit harness connector terminals.
4. If OK, check harness for short to ground and short to power.
5. If OK, check continuity between body ground and CVT assembly.
6. Reinstall any part removed.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
Terminal Wire color Item Condition Data (Approx.)
11 L Step motor A Within 2 seconds after ignition switch ON, the time measure-
ment by using the pulse width measurement function (Hi level)
of CONSULT-II.*1
CAUTION:
Connect the diagnosis data link cable to the vehicle diag-
nosis connector.
*1: A circuit tester cannot be used to test this item.30.0 msec
12 Y Step motor B10.0 msec
20 W Step motor C30.0 msec
21 P Step motor D10.0 msec
Item name Condition Display value (Approx.)
STM STEP
During driving−20 step - 180 step
SMCOIL A
Changes ON⇔OFF. SMCOIL B
SMCOIL C
SMCOIL D
SCIA4516E
Item Connector Terminal Continuity
TCM E31 11
Ye s
CVT unit harness connector F46 6
TCM E31 12
Ye s
CVT unit harness connector F46 7
TCM E31 20
Ye s
CVT unit harness connector F46 8
TCM E31 21
Ye s
CVT unit harness connector F46 9
SCIA4695E

DTC P1777 STEP MOTOR - CIRCUIT
CVT-167
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CVT
Revision: June 20062007 Versa
3. CHECK STEP MOTOR
Check step motor. Refer to CVT-167, "
Component Inspection" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform CVT-164, "
DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 5.
5. CHECK TCM
1. Check TCM input/output signals. Refer to CVT-54, "
TCM Input/Output Signal Reference Values" .
2. If NG, re-check TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
Component InspectionUCS0063P
STEP MOTOR
1. Turn ignition switch OFF.
2. Disconnect CVT unit harness connector.
3. Check resistance between CVT unit harness connector termi-
nals and ground.
4. If NG, replace the transaxle assembly. Refer to CVT-207, "
Removal and Installation" .
Name Connector TerminalResistance
(Approx.)
Step motor F466 - 7
30 Ω
8 - 9
6 - Ground
15 Ω 7 - Ground
8 - Ground
9 - Ground
SCIA4696E

CVT-168
DTC P1778 STEP MOTOR - FUNCTION
Revision: June 20062007 Versa
DTC P1778 STEP MOTOR - FUNCTIONPFP:31947
DescriptionUCS0063Q

The step motor is included in the control valve assembly.

The step motor's 4 aspects of ON/OFF change according to the signal from TCM. As a result, the flow of
line pressure to primary pulley is changed and pulley ratio is controlled.

This diagnosis item is detected when electrical system is OK, but mechanical system is NG.

This diagnosis item is detected when the state of the changing the speed mechanism in unit does not
operate normally.
CONSULT-II Reference ValueUCS0063R
Remarks: Specification data are reference values.
On Board Diagnosis LogicUCS0063S

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1778 STEP MOTR/FNC” with CONSULT-II is detected under the following con-
ditions.
–When not changing the pulley ratio according to the instruction of TCM.
Possible CauseUCS0063T
Step mot or
DTC Confirmation ProcedureUCS0063U
CAUTION:

Always drive vehicle at a safe speed.

Before starting “DTC Confirmation Procedure”, confirm “Hi” or “Mid” or “Low” fixation by “PRI
SPEED” and “VEHICLE SPEED” on “DATA MONITOR MODE”.

If hi-geared fixation occurred, go to CVT-169, "Diagnostic Procedure" .
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, touch “ERASE” on “SELF-DIAG RESULTS” and then perform the following procedure to con-
firm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
2. Make sure that output voltage of CVT fluid temperature sensor
is within the range below.
ATF TEMP SEN: 1.0 - 2.0 V
If out of range, drive the vehicle to decrease the voltage
(warm up the fluid) or stop engine to increase the voltage
(cool down the fluid)
3. Select “DATA MONITOR” mode for “TRANSMISSION” with
CONSULT-II.
4. Start engine and maintain the following conditions for at least 30
consecutive seconds.
TEST START FROM 0 km/h (0 MPH)
CONSTANT ACCELERATION: Keep 30 sec or more
VEHICLE SPEED: 10 km/h (6 MPH) or more
ACC PEDAL OPEN: More than 1.0/8
RANGE: “D” position
ENG SPEED: 450 rpm or more
5. If DTC is detected, go to CVT-169, "
Diagnostic Procedure" .
Item name Condition Display value (Approx.)
STM STEP
During driving−20 step - 180 step
GEAR RATIO2.56 - 0.43
BCIA0031E

DTC P1778 STEP MOTOR - FUNCTION
CVT-169
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Revision: June 20062007 Versa
WITH GST
Follow the procedure “WITH CONSULT-II”.
Diagnostic ProcedureUCS0063V
1. CHECK STEP MOTOR
With CONSULT-II
It is monitoring whether “GEAR RATIO: 2.56 - 0.43” changes similarly to “STM STEP: −20 - 180” by DATA
MONITOR mode. Refer to CVT-64, "
DATA MONITOR MODE" .
Without CONSULT-II
Inspect the engine speed (rise and descend), vehicle speed, throttle position, and check shift change. Refer to
CVT-210, "
Vehicle Speed When Shifting Gears" .
OK or NG
OK >>INSPECTION END
NG >> Replace the transaxle assembly. Refer to CVT-207, "
Removal and Installation" .

CVT-170
OVERDRIVE CONTROL SWITCH
Revision: June 20062007 Versa
OVERDRIVE CONTROL SWITCHPFP:25130
DescriptionUCS006XK

Overdrive control switch is installed to the selector lever.

O/D OFF indicator turns ON, and overdrive driving activates when pressing the overdrive control switch
while driving in “D” position. O/D OFF indicator turns OFF, and “D” position driving starts when pressing
the overdrive control switch while driving in the overdrive-off mode. Shifting the selector lever in any posi-
tion other than “D” releases the overdrive-off mode.
CONSULT-II Reference ValueUCS006KP
Item name Condition Display value
SPORT MODE SWWhile pushing overdrive cancel switch ON
Other conditions OFF

OVERDRIVE CONTROL SWITCH
CVT-171
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CVT
Revision: June 20062007 Versa
Wiring Diagram — CVT — ODSWUCS006KQ
BCWA0686E

CVT-172
OVERDRIVE CONTROL SWITCH
Revision: June 20062007 Versa
TCM terminal data are reference values, measured between each terminal and ground.
Diagnostic ProcedureUCS006KR
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis check. Refer to CVT-60, "
SELF-DIAGNOSTIC RESULT MODE" .
Is any malfunction of the
“U1000 CAN COMM CIRCUIT” indicated in the results?
YES >> Check CAN communication line. Refer to CVT-68, "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK OVERDRIVE CONTROL SWITCH SIGNAL
With CONSULT-II
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
3. Read out ON/OFF switching action of the “SPORT MODE SW”.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. CHECK OVERDRIVE CONTROL SWITCH
Check overdrive control switch. Refer to CVT-174, "
Component Inspection"
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK SELF-DIAGNOSTIC RESULTS (COMBINATION METER)
Perform self-diagnosis check. Refer to DI-13, "
Self-Diagnosis Mode of Combination Meter" .
Is any malfunction detected by self-diagnostic?
YES >> Check the malfunctioning system.
NO - 1 >> With intelligent key: GO TO 5.
NO - 2 >> Without intelligent key: GO TO 6.
TerminalWire
colorItem Condition Data (Approx.)
5 L CAN-H — —
6 P CAN-L — —
Item name Condition Display value
SPORT MODE SWWhile pushing overdrive
cancel switchON
Other conditions OFF
SCIA4517E

OVERDRIVE CONTROL SWITCH
CVT-173
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Revision: June 20062007 Versa
5. CHECK OVERDRIVE CONTROL SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect CVT device connector and combination meter connector.
3. Check continuity between CVT device harness connector (A)
terminal and combination meter harness connector (B) terminal.
4. Check continuity between CVT device harness connector termi-
nal and ground.
5. If OK, check harness for short to ground and short to power.
6. Reinstall any part removed.
OK or NG
OK >>INSPECTION END
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
6. CHECK OVERDRIVE CONTROL SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect CVT device connector and combination meter connector.
3. Check continuity between CVT device harness connector (A)
terminal and combination meter harness connector (B) terminal.
4. Check continuity between CVT device harness connector termi-
nal and ground.
5. If OK, check harness for short to ground and short to power.
6. Reinstall any part removed.
OK or NG
OK >>INSPECTION END
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
Item Connector Terminal Continuity
CVT device harness connector M38 1
Ye s
Combination meter harness
connectorM24 8
SCIA7949E
Item Connector Terminal Continuity
CVT device harness connector M38 2 - ground Yes
SCIA7950E
Item Connector Terminal Continuity
CVT device harness connector M38 1
Ye s
Combination meter harness
connectorM24 8
SCIA7951E
Item Connector Terminal Continuity
CVT device harness connector M38 2 - ground Yes
SCIA7952E