P1778

P1778 STEP MOTOR

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 .

1. PREPARATION BEFORE WORK

If another "DTC CONFIRMATION PROCEDURE" occurs just before, turn ignition switch OFF and wait for at least 10 seconds, then perform the next test.
- GO TO 2.

2. CHECK DTC DETECTION

With CONSULT
1.Start the engine.
2.Select "Data Monitor" in "TRANSMISSION".
3.Select "RANGE", "ATF TEMP SEN", "ACC PEDAL OPEN", "PRI SPEED" and "VEHICLE SPEED".
4.Drive the vehicle.
5.Maintain the following condition for 5 seconds or more.





6.Stop the vehicle.
7.Select "Self Diagnostic Results" in "TRANSMISSION".
With GST
Follow the procedure "With CONSULT".
Is "P1778" detected?
YES- Go to .
NO- INSPECTION END


Diagnosis Procedure


1. CHECK STEP MOTOR SYSTEM

Check step motor system. P1777.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair or replace damaged parts. Line Pressure Test.

2. CHECK PRIMARY SPEED SENSOR SYSTEM

Check primary speed sensor system. P0715.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace damaged parts.

3. CHECK SECONDARY SPEED SENSOR SYSTEM

Check secondary speed sensor system. P0720.
Is the inspection result normal?
YES- GO TO 4.
NO- Repair or replace damaged parts.

4. CHECK INTERMITTENT INCIDENT

Intermittent Incident.
Is the inspection result normal?
YES- Replace transaxle assembly. Removal And Installation (2WD) or Removal And Installation (AWD).
NO- Repair or replace damaged parts.