CVT RE0F10A

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 controlled


DTC Logic


DTC DETECTION LOGIC







DTC CONFIRMATION PROCEDURE


CAUTION:
Always drive vehicle at a safe speed.
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.Start engine.
2.Drive vehicle for at least 5 consecutive seconds.
3.Perform "SELF-DIAG RESULTS" mode for "TRANSMISSION".
With GST
Follow the procedure "With CONSULT".
Is "P1777" detected?
YES- Go to "Diagnosis Procedure".
NO- Check intermittent incident. Intermittent Incident.


Diagnosis Procedure


1. CHECK STEP MOTOR CIRCUIT (PART 1)






1.Turn ignition switch OFF.
2.Disconnect TCM harness connector.
3.Check resistance between TCM harness connector terminals.





Is the inspection result normal?
YES- GO TO 2.
NO- GO TO 3.

2. CHECK STEP MOTOR CIRCUIT (PART 2)

Check resistance between TCM harness connector terminals and ground.





Is the inspection result normal?
YES- Check intermittent incident. Intermittent Incident.

NO- GO TO 3.

3. CHECK STEP MOTOR

1.Disconnect CVT unit connector.
2.Check resistance between CVT unit connector terminals.





3.Check resistance between CVT unit connector terminals and ground.





Is the inspection result normal?
YES- GO TO 4.
NO- GO TO 6.

4. CHECK CIRCUIT BETWEEN TCM AND CVT UNIT (STEP MOTOR) (PART 1)

Check continuity between TCM harness connector terminals and CVT unit harness connector terminals.





Is the inspection result normal?
YES- GO TO 5.
NO- Repair or replace damaged parts.

5. CHECK CIRCUIT BETWEEN TCM AND CVT UNIT (STEP MOTOR) (PART 2)

Check continuity between TCM harness connector terminals and ground.





Is the inspection result normal?
YES- Check intermittent incident. Intermittent Incident.
NO- Repair or replace damaged parts.

6. CHECK TERMINAL CORD ASSEMBLY (PART 1)

1.Remove terminal cord assembly. Exploded View.
2.Check continuity between CVT unit harness connector terminals and control valve harness connector terminals.





Is the inspection result normal?
YES- GO TO 7.
NO- Repair or replace damaged parts.

7. CHECK TERMINAL CORD ASSEMBLY (PART 2)

Check terminal cord assembly harness cladding for damage.
Is the inspection result normal?
YES- GO TO 8.
NO- Repair or replace damaged parts.

8. CHECK DTC (TCM)

With CONSULT
1.Perform DTC CONFIRMATION PROCEDURE. CVT RE0F10A Torque Converter.
2.Perform "SELF-DIAG RESULTS" mode for "TRANSMISSION".
Is only "P1777" detected?
YES-1 ("P1777" only)-There is a malfunction of the CVT fluid temperature sensor. Replace the control valve. Removal And Installation.
YES-2 ("P1777" and "P0725"/"P1777" and "U1000"/"P1777", "P0725" and "U1000" are detected)-Replace the control valve. Removal And Installation.
YES-3 (Other than YES-1 and YES-2)-Replace the transaxle assembly. Removal And Installation.
NO- Check intermittent incident. Intermittent Incident.