CVT RE0F09B Step Motor

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 "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

With CONSULT
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.





4.Start engine and maintain the following conditions for at least 30 consecutive seconds.





With GST
Follow the procedure "With CONSULT".
Is "P1778" detected?
YES- Go to "Diagnosis Procedure".
NO- Check intermittent incident. Intermittent Incident.


Diagnosis Procedure


1. CHECK STEP MOTOR SYSTEM

Check step motor system. CVT RE0F09B.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair or replace damaged parts.

2. CHECK PRIMARY SPEED SENSOR SYSTEM

Check primary speed sensor system. CVT RE0F09B Input Speed Sensor A.
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. CVT RE0F09B Output Speed Sensor.
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. Exploded View.
NO- Repair or replace damaged parts.