Nissan Versa

 Sedan Service Manual

Steering » Steering control system (STC) » C1601 Battery power supply
Diagnosis Procedure

Regarding Wiring Diagram information, refer to STC "Wiring Diagram".

1.CHECK EPS CONTROL UNIT GROUND CIRCUIT

1. Turn ignition switch OFF.
2. Disconnect EPS control unit harness connector.
3. Check continuity between EPS control unit harness connector terminal and ground. 
4. Connect EPS control unit harness connector.

Is the inspection result normal?

YES >> GO TO 2.

NO >> Repair open circuit or short to ground or short to power in harness or connectors.

2.CHECK EPS CONTROL UNIT POWER SUPPLY CIRCUIT (1)

    1.   Check voltage between EPS control unit harness connector terminal and ground.

    2.   Turn ignition switch ON.

CAUTION: Never start the engine.

    3.   Check voltage between EPS control unit harness connector and ground. 

Is the inspection result normal?

YES >> GO TO 4.

NO >> GO TO 3.

3.CHECK EPS CONTROL UNIT POWER SUPPLY CIRCUIT (2)

1. Turn ignition switch OFF.
2. Check the 10A fuse (No. 5).
3. Check the harness for open or short between EPS control unit harness connector M53 terminal 4 and the 10A fuse (No. 5).

Is the inspection result normal?

YES >> Perform the trouble diagnosis for ignition power supply circuit. Refer to PG "Wiring Diagram - Ignition Power Supply -".

NO >> Repair or replace malfunctioning component.

4.CHECK EPS CONTROL UNIT POWER SUPPLY CIRCUIT (3)

1. Turn ignition switch OFF.
2. Check voltage between EPS control unit harness connector terminal and ground. 

    3.   Turn ignition switch ON.

CAUTION: Never start the engine.

    4.   Check voltage between EPS control unit harness connector and ground. 

Is the inspection result normal?

YES >> GO TO 6.

NO >> GO TO 5.

5.CHECK EPS CONTROL UNIT POWER SUPPLY CIRCUIT (4)

1. Turn ignition switch OFF.
2. Check the 60A fusible link (J).
3. Check the harness for open or short between EPS control unit harness connector E23 terminal 17 and the 60A fusible link (J).

Is the inspection result normal?

YES >> Perform the trouble diagnosis for power supply circuit. Refer to PG "Wiring Diagram - Battery Power Supply -".

NO >> Repair or replace malfunctioning component.

6.CHECK CONNECTOR

1. Turn ignition switch OFF.
2. Disconnect torque sensor harness connector.
3. Check terminal for deformation, disconnection, looseness, and so on. If any malfunction is found, repair or replace terminal.

Is the inspection result normal?

YES >> Replace EPS control unit. Refer to STC "Removal and Installation".

NO >> Repair or replace malfunctioning component.

DTC Logic

Diagnosis Procedure