Nissan Altima 2007-2012 Service Manual: P1778 step motor - function
Description
• 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.
DTC Logic
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
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 TM-187, "Diagnosis Procedure". NOTE: If “DTC CONFIRMATION PROCEDURE” has been previously performed, always turn ignition switch OFF.
Then wait at least 10 seconds before performing the next test.
1.CHECK DTC DETECTION
1. Turn ignition switch ON.
2. Select “DATA MONITOR”.
3. 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)
4. Start engine and maintain the following conditions for at least 30 consecutive seconds.
Follow the procedure “With CONSULT-III”.
Is “P1778 STEP MOTR/FNC” detected? YES >> Go to TM-187, "Diagnosis Procedure".
NO >> Check intermittent incident. Refer to GI-42, "Intermittent Incident".
Diagnosis Procedure
1.CHECK STEP MOTOR SYSTEM
Check step motor system. Refer to TM-184, "Description".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace damaged parts.
2.CHECK INPUT SPEED SENSOR (PRIMARY SPEED SENSOR) SYSTEM
Check input speed sensor (primary speed sensor) system. Refer to TM-135, "Description".
Is the inspection result normal? YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK OUTPUT SPEED SENSOR (SECONDARY SPEED SENSOR) SYSTEM
Check output speed sensor (secondary speed sensor) system. Refer to TM-138, "Description".
Is the inspection result normal? YES >> GO TO 4.
NO >> Repair or replace damaged parts.
4.DETECT MALFUNCTIONING ITEMS
Check TCM connector pin terminals for damage or loose connection with harness connector.
Is the inspection result normal? YES >> Replace TCM. Refer to TM-254, "Exploded View".
NO >> Repair or replace damaged parts.
P1777 step motor
Description
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
...
Shift lock system
Description
The selector lever cannot be shifted from “P” position to any other position
unless the ignition switch is in the
ON position and the brake pedal is depressed.
Wiring Diagram - C ...
Other materials:
Light reminder warning chime
System Diagram
System Description
DESCRIPTION
With ignition switch in OFF or ACC position, driver door open, and lighting
switch in 1ST or 2ND position, the
light warning chime will sound.
• BCM detects ignition switch in OFF or ACC position, door switch LH ON, and
lighting switch i ...
On board diagnostic (OBD) System
Diagnosis Description
INTRODUCTION
The ECM has an on board diagnostic system, which detects malfunctions related
to engine sensors or actuators.
The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in t ...
Fuel pressure
Inspection
FUEL PRESSURE RELEASE
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in “WORK SUPPORT” mode with CONSULT-III.
3. Start engine.
4. After engine stalls, crank it 2 or 3 times to release all fuel pressure.
5. Turn ignition switch OFF.
1. Remove fuel ...
