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


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-364, "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.


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”.


Follow the procedure “With CONSULT-III”.

Is “P1778 STEP MOTR/FNC” detected? YES >> Go to TM-364, "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-361, "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-313, "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-318, "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-430, "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 position indicator circuit
    Description • TCM sends position indicator signals to combination meter by CAN communication line. • Manual mode switch position is indicated on shift position indicator. Component F ...

    Other materials:

    DLC branch line circuit
    Diagnosis Procedure INSPECTION PROCEDURE 1.CHECK CONNECTOR 1. Turn the ignition switch OFF. 2. Disconnect the battery cable from the negative terminal. 3. Check the terminals and connectors of the data link connector for damage, bend and loose connection (connector side and harness side ...

    Replacing
    Replace the wiper blades if they are worn. 1. Lift the wiper arm away from the windshield. 2 Push the release tab, then move the wiper blade down the wiper arm to remove. 3 Remove the wiper blade. 4. Insert the new wiper blade onto the wiper arm until it clicks into place. 5. Rotate the w ...

    P0603 ECM Power supply
    Description Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc. DTC Logic DTC DETECTION LOGIC DTC CONFIRMAT ...