Nissan Juke F15. Manual - part 1187

STC-4

< PRECAUTION >

PRECAUTIONS

• Turbocharger cooling pump may operate in a few minutes after the ignition switch is turned OFF.

• Example of high-load driving

- Driving for 30 minutes or more at 140 km/h (86 MPH) or more.

- Driving for 30 minutes or more on a steep slope.

• For vehicles with the 2-batteries, be sure to connect the main battery and the sub battery before turning ON

the ignition switch.

NOTE:

If the ignition switch is turned ON with any one of the terminals of main battery and sub battery discon-

nected, then DTC may be detected.

• After installing the 12V battery, always check "Self Diagnosis Result" of all ECUs and erase DTC.

NOTE:

The removal of 12V battery may cause a DTC detection error.

Service Notice or Precautions for EPS System

INFOID:0000000012199910

• Check the following item when performing the trouble diagnosis.

- Check any possible causes by interviewing the symptom and it

′s condition from the customer if any malfunc-

tion, such as EPS warning lamp is turned ON, occurs.

- Check if air pressure and size of tires are proper, the specified part is used for the steering wheel, and con-

trol unit is genuine part.

- Check if the connection of steering column assembly and steering gear assembly is proper (there is not

looseness of mounting bolts, damage of rods, boots or sealants, and leakage of grease, etc).

- Check if the wheel alignment is adjusted properly.

- Check if there is any damage or modification to suspension or body resulting in increased weight or altered

ground clearance.

- Check if installation conditions of each link and suspension are proper.

- Check if the battery voltage is proper.

- Check connection conditions of each connector are proper.

- Before connecting or disconnecting the EPS control unit harness

connector, turn ignition switch “OFF” and disconnect battery

ground cable. Because battery voltage is applied to EPS control

unit even if ignition switch is turned “OFF”.

- When connecting or disconnecting pin connectors into or from

EPS control unit, take care not to damage pin terminals (bend or

break).

- When connecting pin connectors, make sure that there are no

bends or breaks on EPS control unit pin terminal.

• During quick steering, rasping noise may be heard from around the

steering wheel. This is not a malfunction. The noise is an operating

noise of the EPS system under normal conditions. If the rasping

noise occurs during slow steering, this may not be an operating

noise of the system. In this case, it is necessary to find out the

location of the noise and repair, if necessary.

SEF289H

SEF291H

COMPONENT PARTS

STC-5

< SYSTEM DESCRIPTION >

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SYSTEM DESCRIPTION

COMPONENT PARTS

Component Parts Location

INFOID:0000000012199911

*: Models with Integrated Control System

Component Description

INFOID:0000000012199912

1.

Multi display unit

*

Refer to 

DMS-4, "Component Parts 

Location"

.

2.

ABS actuator and electric unit (con-
trol unit)
Refer to 

BRC-9, "Component Parts 

Location"

3.

ECM
Refer to 

EC-27, "ENGINE CON-

TROL SYSTEM : 
Component Parts Location"

4.

Combination meter
Refer to 

MWI-6, "METER SYSTEM : 

Component Parts Location"

.

5.

EPS warning lamp
(In combination meter)

6.

EPS motor

7.

EPS control unit

8.

Reduction gear

9.

Torque sensor

A.

Steering column assembly

JSGIA0830GB

Components parts

Reference

EPS control unit

STC-6, "EPS Control Unit"

EPS motor

STC-6, "EPS Motor"

Torque sensor

STC-6, "Torque Sensor"

Reduction gear

STC-6, "Reduction Gear"

EPS warning lamp

STC-7, "EPS SYSTEM : System Description"

STC-6

< SYSTEM DESCRIPTION >

COMPONENT PARTS

*: Models with Integrated Control System

EPS Control Unit

INFOID:0000000012199913

• EPS control unit performs an arithmetical operation on data, such as steering wheel turning force (sensor

signal) from the torque sensor, vehicle speed signal, etc. Then it generates an optimum assist torque signal

to the EPS motor according to the driving condition.

• EPS control unit decreases the output signal to EPS motor while extremely using the power steering func-

tion (e.g., full steering) consecutively for protecting EPS motor and EPS control unit (Overload protection

control).

• In SPORT mode, changes the steering assist characteristic to enhance a stable steering feel according to

the mode signals from multi display unit via CAN communication. (Models with Integrated Control System)

EPS Motor

INFOID:0000000012199914

EPS motor provides the assist torque by the control signal from EPS control unit.

Torque Sensor

INFOID:0000000012199915

Torque sensor detects the steering torque, and transmit the signal to EPS control unit.

Reduction Gear

INFOID:0000000012199916

Reduction gear increases the assist torque provided from EPS motor with worm gears, and outputs to the col-

umn shaft.

ECM

• Transmits mainly the following signals to EPS control unit via 

CAN communication. 

- Engine status signal 

ABS actuator and electric unit (control unit)

• Transmits mainly the following signal to EPS control unit via 

CAN communication. 

- Vehicle speed signal 

Combination meter

• Transmits mainly the following signal to EPS control unit via 

CAN communication. 

- Vehicle speed signal 

• Turns ON the EPS warning lamp according to the signal from 

EPS control unit via CAN communication.

Multi display unit

*

• Transmits mainly the following signals to EPS control unit via 

CAN communication. 

- ECO mode signal 
- NORMAL mode signal 
- SPORT mode signal 

Components parts

Reference

SYSTEM

STC-7

< SYSTEM DESCRIPTION >

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EPS SYSTEM
EPS SYSTEM : System Description

INFOID:0000000012199917

• EPS control unit performs an arithmetical operation on data, such

as steering wheel turning force (sensor signal) from the torque

sensor, vehicle speed signal, etc. Then it generates an optimum

assist torque signal to the EPS motor according to the driving con-

dition.

• In case of an error in the electrical system, the fail-safe function

stops output signals to the EPS motor. Refer to 

STC-8, "EPS SYS-

TEM : Fail-Safe"

.

• EPS control unit decreases the output signal to EPS motor while

extremely using the power steering function (e.g., full steering)

consecutively for protecting EPS motor and EPS control unit

(Overload protection control). Refer to 

STC-8, "EPS SYSTEM :

Protection Function"

.

• Extensive steering at low speed will cause the EPS control unit

and EPS motor to heat up, once temperature reaches critical point

EPS control unit will reduce current to reduce heat up. System will

recover as temperature lowers (reduced or no assistance).

• In SPORT mode, changes the steering assist characteristic to

enhance a stable steering feel according to the mode signals from

multi display unit via CAN communication. (Models with Integrated

Control System)

SYSTEM DIAGRAM

Multi display unit is applied to models with Integrated Control System.

INPUT/OUTPUT SIGNAL

Communicates the signal from each control unit via CAN communication. 

JSGIA1102GB

JSGIA0833GB

Control unit

Signal status

ECM

• Transmits mainly the following signals to EPS control unit via CAN communication. 
- Engine status signal 

ABS actuator and electric unit (con-
trol unit)

• Transmits mainly the following signals to EPS control unit via CAN communication. 
- Vehicle speed signal