2003 NISSAN TEANA ignition

DTC P1778 STEP MOTOR - FUNCTION
CVT-157
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CVT

DTC P1778 STEP MOTOR - FUNCTIONPFP:31947
DescriptionBCS001M0

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 ValueBCS001M1
Remarks: Specification data are reference values.
On Board Diagnosis LogicBCS001M2
Diagnostic trouble code “P1778 STEP MOTR/FNC” with CONSULT-II is detected under the following condi-
tions.

When not changing the pulley ratio according to the instruction of TCM.
Possible CauseBCS001M3
Ste p mo to r
DTC Confirmation ProcedureBCS001M4
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-158, "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-158, "
Diagnostic Procedure" .
Item name Condition Display value (Approx.)
STM STEP
During driving−20 step - 190 step
GEAR RATIO2.37 - 0.43
BCIA0031E

CVT-164
TROUBLE DIAGNOSIS FOR SYMPTOMS

CVT Indicator Lamp Does Not Come OnBCS001MB
SYMPTOM:
CVT indicator lamp does not come on for about 2 seconds when turning ignition switch to ON.
DIAGNOSTIC PROCEDURE
1. CHECK CAN COMMUNICATION LINE
Perform the self-diagnosis check. Refer to CVT-47, "
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-53, "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK TCM POWER SOURCE
1. Turn ignition switch ON.
2. Check voltage between TCM connector terminals and ground.
Refer to CVT-135, "
Wiring Diagram — CVT — POWER" .
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING ITEM
Check the following.

Harness for short or open between ignition switch and TCM connector terminal 10, 19
Refer to CVT-135, "
Wiring Diagram — CVT — POWER" .

10A fuse (No.83, located in the IPDM E/R). Refer to CVT-135, "Wiring Diagram — CVT — POWER" .

Ignition switch. Refer to PG-3, "POWER SUPPLY ROUTING CIRCUIT" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK TCM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect TCM connector.
3. Check continuity between TCM connector terminals and ground.
Refer to CVT-135, "
Wiring Diagram — CVT — POWER" .
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
Name Connec-
tor Terminal Voltage (Approx.)
Power supply F10610 Battery voltage
19 Battery voltage
SCIA4737E
Name Connec-
tor Terminal Continuity
Ground F10725
Ye s
48
SCIA2671E

TROUBLE DIAGNOSIS FOR SYMPTOMS
CVT-165
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CVT

5. DETECT MALFUNCTIONING ITEM
Check the following.

Harness and fuse for short or open between ignition switch and CVT indicator lamp
Refer to PG-3, "
POWER SUPPLY ROUTING CIRCUIT" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6. CHECK SYMPTOM
Check again. Refer to CVT-37, "
Check Before Engine Is Started" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7. CHECK COMBINATION METERS
Check combination meters. Refer to DI-4, "
COMBINATION METERS" .
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
Engine Cannot Be Started in “P” or “N” PositionBCS001MC
SYMPTOM:

Engine cannot be started with selector lever in “P” or “N” position.

Engine can be started with selector lever in “D”, “M” or “R” position.
DIAGNOSTIC PROCEDURE
1. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis check. Refer to CVT-47, "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate PNP switch circuit or start signal circuit?
YES >> Check PNP switch circuit or start signal circuit. Refer to CVT-62, "DTC P0705 PARK/NEUTRAL
POSITION SWITCH" or CVT-56, "DTC P0615 START SIGNAL CIRCUIT" .
NO >> GO TO 2.
2. CHECK CVT POSITION
Check CVT position. Refer to CVT-179, "
Checking of CVT Position"
OK or NG
OK >> GO TO 3.
NG >> Adjust CVT position. Refer to CVT-178, "
Adjustment of CVT Position" .
3. CHECK STARTING SYSTEM
Check starting system. Refer to SC-14, "
STARTING SYSTEM" .
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.

TROUBLE DIAGNOSIS FOR SYMPTOMS
CVT-167
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CVT

5. CHECK TCM
1. Check TCM input/output signal. Refer to CVT-40, "
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 >> Replace the transaxle assembly. Refer to CVT-193, "Removal and Installation" .
NG >> Repair or replace damaged parts.
Large Shock “N” → “R” PositionBCS001MF
SYMPTOM:
There is large shock when shifting from “N” to “R” position.
DIAGNOSTIC PROCEDURE
1. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis check. Refer to CVT-47, "
SELF-DIAGNOSTIC RESULT MODE" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system. Refer to CVT-47, "Display Items List" .
NO >> GO TO 2.
2. CHECK ENGINE IDLE SPEED
Check engine idle speed. Refer to EC-387, "
Idle Speed and Ignition Timing Check" .
OK or NG
OK >> GO TO 3.
NG >> Repair.
3. CHECK CVT FLUID LEVEL
Check CVT fluid level. Refer to CVT-13, "
Checking CVT Fluid" .
OK or NG
OK >> GO TO 4.
NG >> Refill CVT fluid.
4. CHECK LINE PRESSURE
Check line pressure at idle. Refer to CVT-33, "
LINE PRESSURE TEST" .
OK or NG
OK >> GO TO 5.
NG >> Check the malfunctioning item. Refer to CVT-34, "
Judgement of Line Pressure Test" .
5. CHECK SYMPTOM
Check again. Refer to CVT-37, "
Check at Idle" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 6.
6. CHECK TCM
1. Check TCM input/output signals. Refer to CVT-40, "
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 >> Replace the transaxle assembly. Refer to CVT-193, "Removal and Installation" .
NG >> Repair or replace damaged parts.

SHIFT CONTROL SYSTEM
CVT-179
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CVT

Checking of CVT PositionBCS001MO
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 whether or not the actual position the selector lever is in matches the position shown
by the shift position indicator and the transaxle body.
5. The method of operating the lever to individual positions cor-
rectly should be as shown in the figure.
6. Confirm the back-up lamps illuminate only when lever is placed
in the “R” position. Confirm the back-up lamps do not illuminate
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.
9. When selector lever is set to manual shift gate, make sure man-
ual mode is displayed on combination meter.
Shift selector lever to “+” and “-” sides, and make sure set shift position changes.
SCIA4595E

CVT-180
CVT SHIFT LOCK SYSTEM

CVT SHIFT LOCK SYSTEMPFP:00000
DescriptionBCS001MP

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

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 the key cylinder, respectively.
Shift Lock System Electrical Parts LocationBCS001MQ
NOTE:
This emergency lever can be used when battery is off ignition key cannot be removed. In the situation like this,
by operating this lever, ignition key can be removed.
1. Stop lamp switch 2. Shift lock control unit
A. Behind Audio Unit B. Key lock solenoid C. Emergency lever
D. Key switch E. Shift lock release button F. Detention switch (shift)
G. Detention switch (key) H. Shift lock solenoid
SCIA7845E

CVT SHIFT LOCK SYSTEM
CVT-183
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Shift Lock Control Unit Reference ValuesBCS001MT
SHIFT LOCK HARNESS CONNECTOR TERMINALS LAYOUT
SHIFT LOCK CONTROL UNIT INSPECTION TABLE
Shift lock control unit terminal data are reference values, measured between each terminal and ground.
NOTE:
Take care that the pointer of circuit tester swings only momentarily because the output time is so short. If the inspection is done with an
oscilloscope, it should be observed that the power source voltage lasts for 3.5 to 10 ms.
SCIA2004E
Terminal
(Wire color)Item Condition Judgement standard
1
(Y/R)Power source Always Battery voltage
2
(L)Detention switch (for
key)When selector lever is not in “P” position with key
inserted or ignition knob switch pushed.Battery voltage
When selector lever is in “P” position with key
inserted.Approx. 0 V
3
(R)Detention switch (for
shift)When selector lever is not in “P” position. Battery voltage
When selector lever is in “P” position. Approx. 0 V
4
(R/G)Stop lamp switchWhen brake pedal is depressed Battery voltage
When brake pedal is released Approx. 0 V
5
(V/W)Vehicle speed signal
(8pulse signal)Speed meter is operatedRefer to DI-13, "
Terminals and Refer-
ence Value for Unified Meter and A/C
Amp." .
6
(G)Ignition signalIgnition switch: except ON Approx. 0 V
Ignition switch: ON Battery voltage
7
(R/W)Shift lock solenoid

When selector lever is in “P” position, brake
pedal is depressed, and ignition switch is ON.

When selector lever is not in “P” position, igni-
tion switch is ON, and vehicle speed is 10 km/h
(6 MPH) or less.

Within 3 minutes, after ignition switch turning to
other position from ON position, while selector
lever is not in “P” position and vehicle speed is
10 km/h (6 MPH) or less.Approx. 0 V
Except the above Battery voltage
8
(B)Ground — Approx. 0 V
9
(G/B)Key lock solenoidWhen selector lever is not “P” position.Battery voltage for approx. 0.1 sec.
(Note)
When selector lever is in “P” position. Approx. 0 V
10
(G/W)Key unlock solenoidWhen selector lever is in “P” position with ignition
switch in except ON position.Battery voltage for approx. 0.1 sec.
(Note)
Except the above. Approx. 0 V

CVT-184
CVT SHIFT LOCK SYSTEM

Component InspectionBCS001MU
SHIFT LOCK SOLENOID
Check operation by applying battery voltage to the CVT device har-
ness connector.
CAUTION:
Be sure to apply the voltage of the correct polarity to the
respective terminals. Otherwise, the part may be damaged.
DETENTION SWITCH (FOR KEY)
Check continuity between terminals of the CVT device harness con-
nector.
DETENTION SWITCH (FOR SHIFT)
Check continuity between terminals of the CVT device harness con-
nector.
KEY LOCK SOLENOID
Key Lock
Check operation by applying battery voltage to ignition knob switch,
key switch and key lock solenoid harness connector terminal.
CAUTION:
Be careful not to cause burnout of the harness.
Connector Terminal
M92 9 (Battery voltage) - 10 (Ground)
SCIA2005E
Condition Connector Terminal Continuity
When selector lever is in “P”
position.
M92 5 - 6No
When selector lever is not in
“P” position.Ye s
SCIA2006E
Condition Connector Terminal Continuity
When selector lever is in “P”
position.
M92 13 - 14No
When selector lever is not in
“P” position.Ye s
SCIA2046E
Connector Terminal
M20 6 (Battery voltage) - 5 (Ground)
SCIA6645E