Nissan Tiida C11. Manual - part 1226

EPS CONTROL UNIT

STC-27

< ECU DIAGNOSIS >

[EPS]

C

D

E

F

H

I

J

K

L

M

A

B

STC

N

O

P

Fail-Safe Function

INFOID:0000000001697717

• If any malfunction occurs in the system, and control unit detects the malfunction, EPS warning lamp on com-

bination meter turns ON to indicate system malfunction.

• When EPS warning lamp is ON, enters a manual steering state. (Control turning force steering wheel

becomes heavy.)

ALGIA0028GB

STC-28

< ECU DIAGNOSIS >

[EPS]

EPS CONTROL UNIT

DTC Index

INFOID:0000000001716730

DTC

Items (CONSULT screen terms)

Reference

C1601

BATTERY POWER SUPPLY

STC-9

C1604

TORQUE SENSOR

STC-11

C1606

EPS MOTOR

STC-13

C1607

EEPROM

STC-15

C1608

EPS CONTROL UNIT

STC-16

C1609

CAN VHCL SPEED

STC-17

C1610

CAN ENG RPM

STC-19

U1000

CAN COMM CIRCUIT

STC-21

EPS SYSTEM SYMPTOMS

STC-29

< SYMPTOM DIAGNOSIS >

[EPS]

C

D

E

F

H

I

J

K

L

M

A

B

STC

N

O

P

SYMPTOM DIAGNOSIS

EPS SYSTEM SYMPTOMS

Symptom Chart

INFOID:0000000001716771

If EPS warning lamp turns ON, perform self-diagnosis. Refer to 

STC-7, "CONSULT-III Function (EPS)"

.

Symptom

Condition

Check item

Reference page

EPS warning lamp does not turn ON when ig-
nition switch to “ON”.
(EPS warning lamp check)

Ignition switch: ON

CAN communication line

STC-30

Combination meter

EPS warning lamp does not turn OFF for sev-
eral seconds after starting the engine

Engine running

CAN communication line

STC-31

Power supply and ground for 
EPS control unit

Torque sensor

EPS motor

Vehicle speed signal

Engine status signal

Combination meter

Steering wheel turning force is heavy or light, 
while driving

• While driving
• Steering wheel turning

CAN communication line

STC-33

Vehicle speed signal

Engine status signal

EPS motor

Steering wheel turning force
(Mechanical malfunction)

Unbalance steering wheel turning force and 
return between right and left, while driving

• While driving
• Steering wheel turning

Wheel alignment

STC-34

Steering wheel turning force
(Mechanical malfunction)

Unbalance steering wheel turning force, 
while driving (Torque variation)

• While driving
• Steering wheel turning

Steering column intermediate 
shaft installation condition 

STC-35

Steering wheel turning force
(Mechanical malfunction)

STC-30

< SYMPTOM DIAGNOSIS >

[EPS]

EPS WARNING LAMP DOES NOT TURN ON

EPS WARNING LAMP DOES NOT TURN ON

Diagnosis Procedure

INFOID:0000000001697733

SYMPTOM:

EPS warning lamp does not turn ON when ignition switch to “ON”.

DIAGNOSTIC PROCEDURE

1.

CHECK SYSTEM FOR CAN COMMUNICATION LINE

Perform self-diagnosis. Refer to 

STC-7, "CONSULT-III Function (EPS)"

 .

Is the “CAN COMM CIRCUIT [U1000]” displayed?

YES

>> Perform trouble diagnosis for CAN communication line. Refer to 

STC-21, "Diagnosis Procedure"

 .

NO

>> GO TO 2.

2.

CHECK EPS CONTROL UNIT

Check EPS control unit input/output signal. Refer to 

STC-22, "EPS Control Unit Input/Output Signal Reference

Value"

 .

OK or NG

OK

>> GO TO 3.

NG

>> Check EPS control unit pin terminals for damage or loose connection with harness connector. If

any items are damaged, repair or replace damaged parts.

3.

SYMPTOM CHECK

Check again.

OK or NG

OK

>> INSPECTION END

NG

>> Replace combination meter. Refer to 

MWI-94, "Removal and Installation"

.