Page 89 of 2267
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NCAT0224S04CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªENGINEº with CONSULT-II.
2) Drive vehicle for at least 5 consecutive seconds.
If the check result is ªNGº, go to ªDiagnostic Procedureº,
AT-89.
With GST
Follow the procedure ªWith CONSULT-IIº.
SAT651J
SAT654J
DTC P1777 STEP MOTOR Ð CIRCUIT
Description (Cont'd)
AT-87
Page 90 of 2267
Wiring Diagram Ð AT Ð STMNCAT0225
YAT208
TCM
(TRANSMISSION
CONTROL MODULE)
: Detectable line for DTC
: Non-detectable line for DTC
CONTROL
VA LV E
(STEP MOTOR)
DTC P1777 STEP MOTOR Ð CIRCUIT
Wiring Diagram Ð AT Ð STM
AT-88
Page 91 of 2267
Diagnostic ProcedureNCAT0226
1 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªONº position.
2. Check ªSELF-DIAGNOSISº with CONSULT-II.
3. If ªCVT SAFE FUNCTIONº activate, refer to ªCVT SAFE FUNCTIONº AT-99.
4. Turn ignition switch to ªOFFº position.
5. Disconnect TCM harness connector.
6. Check continuity between terminal 2, 3, 4, 5 and TCM harness connector terminal 11, 12, 20, 21.
Continuity should exist.
SAT655J
Step motor connector
If OK, check harness for short to ground and short to power.
7. Reinstall any part removed.
OK or NG
OK©GO TO 2.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
2 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-91.
OK or NG
OK©INSPECTION END
NG©1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness con-
nector.
DTC P1777 STEP MOTOR Ð CIRCUIT
Diagnostic Procedure
AT-89
Page 92 of 2267
Component Inspection=NCAT0227STEP MOTORNCAT0227S01Resistance CheckNCAT0227S0101ICheck resistance between terminals.
Control valve Terminal No. Resistance (Approx.)
Step motor2 and 3
28W
4 and 5
2 and ground
14W 3 and ground
4 and ground
5 and ground
SAT690J CVT fluid pressure sensor connector
DTC P1777 STEP MOTOR Ð CIRCUIT
Component Inspection
AT-90
Page 93 of 2267

DescriptionNCAT0228IThe step motor is ON/OFF of 4 aspects changes according to
the signal from TCM.
As a result, the flow of line pressure to primary pulley is
changed and pulley ratio is controlled.
IThis diagnosis item detects when electrical system is OK but,
mechanical system is NG.
IThis diagnosis item detects when the state that the changing
the speed mechanism in unit does not operate normally.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NCAT0228S01It is monitoring whether ªCVT RATIO: 2.32 - 0.47º changes similarly
to ªPLY CONT STEP: 3 - 200º by DATA MONITOR mode.
ON BOARD DIAGNOSIS LOGICNCAT0228S03
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: STEP MOTOR/FNCTN
When not changing the speed according
to the instruction of TCM.IStep motor
: P1778
: MI Code No. 1778
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NCAT0228S04CAUTION:
IAlways drive vehicle at a safe speed.
IBe careful not to rev engine into the red zone on the
tachometer.
IBefore start ªDIAGNOSTIC TROUBLE CODE (DTC) CON-
FIRMATION PROCEDUREº, confirm ªHiº or ªMidº or
ªLowº fixation by ªI/P PULLY SPDº and ªVHCL SPEED SEº
on ªDATA MONITOR MODEº.
IIf hi-geared fixation, go to diagnostic procedure soon.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªCVTº with CONSULT-II.
SAT651J
SAT971J
DTC P1778 STEP MOTOR Ð FUNCTION
Description
AT-91
Page 94 of 2267
2) Make sure that output voltage of CVT fluid temperature sne-
sor is within the range below.
FLUID TEMP SEN: 0.5 - 1.5V
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 ªENGINEº mode for ªENGINEº 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
VHCL SPEED SE: 10 km/h (6 MPH) or more
THRTL POS SEN: More than 1.3V
Selector lever: D position
ENG SPEED: 450 rpm or more
If the check result is NG, go to ªDIAGNOSTIC PROCEDUREº,
AT-93.
With GST
Follow the procedure ªWith CONSULT-IIº.
SAT654J
DTC P1778 STEP MOTOR Ð FUNCTION
Description (Cont'd)
AT-92
Page 95 of 2267
Diagnostic ProcedureNCAT0230
1 CHECK STEP MOTOR
IIt is monitoring whether ªCVT ratio: 2.32 - 0.47º changes similarly to ªPLY CONT STEP: -3 - 200º by DATA MONITOR mode.
IIf no CONSULT-II, inspect the engine speed (rise and descend) about vehicle speed and throttle opening angle, and check shift
change.
OK or NG
OK©INSPECTION END
NG©Replace CVT assembly.
DTC P1778 STEP MOTOR Ð FUNCTION
Diagnostic Procedure
AT-93
Page 96 of 2267

DescriptionNCAT0232IThe CVT fluid pressure sensor detects line pressure of CVT,
and sends TCM the signal.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NCAT0232S01Remarks: Specification data are reference values.
Monitor item Condition Specification
CVT fluid pressure sensorThrottle valve fully closed (PL Duty: 4%)
"
Throttle valve fully depressed
(PL Duty: 94%)Approx. 1.0 V
"
Approx. 4.0 V
TCM TERMINALS AND REFERENCE VALUENCAT0232S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
37 W/G
CVT fluid pressure
sensor
When engine runs at idle speed.Approx. 1.0 V
When engine runs at stall speed.Approx. 4.0V
42 B
ÐÐ
46 P/LÐ4.5 - 5.5 V
ON BOARD DIAGNOSIS LOGICNCAT0232S03
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: LINE PRESS SEN
TCM receives an excessively low or high
voltage from the step motor.IHarness or connectors
(The sensor circuit is open or shorted.)
ICVT fluid pressure sensor
: P1791
: MI Code No. 1791
DTC P1791 CVT FLUID PRESSURE SENSOR
Description
AT-94