
STC-8
< ECU DIAGNOSIS INFORMATION >
EPS CONTROL UNIT
ECU DIAGNOSIS INFORMATION
EPS CONTROL UNIT
Reference ValueINFOID:0000000012431945
VALUES ON THE DIAGNOSIS TOOL
CAUTION:
The output signal indicates the EPS control unit calculation data. The normal values will be displayed
even in the event that the output circuit (harness) is open.
*1: Almost in accordance with the value of “MOTOR S IG”. It is not a malfunction though these values are not
accorded when steering quickly.
*2: A fixed value is indicated regardless of steering turning.
*3: Normally displays 100%. In case of an excessive stat ionary steering, the assist curvature gradually falls.
However, it returns to 100% when left standing.
*4: It is not a malfunction, though it might not be co rresponding just after ignition switch in turned ON.
Monitor item Data monitor
Condition Display value
BATTERY VOLT Ignition switch: ON Battery voltage
TORQUE SENSOR Engine running Steering wheel: Not
steering (There is
no steering force) Approx. 0 Nm
Steering wheel: Right turn Positive value (Nm)
Steering wheel: Left turn Negative value (Nm)
MOTOR CURRENT Engine running Steering wheel: Not
steering (There is
no steering force) Approx. 0 A
Steering wheel: Right or left turn Displays consumption current of
EPS motor (A)
*1
MOTOR SIG
Engine runningSteering wheel: Not
steering (There is
no steering force) Approx. 0 A
Steering wheel: Right turn Positive value (A)
Steering wheel: Left turn Negative value (A)
ASSIST TORQUE Engine running Approx. 0 Nm
*2
C/U TEMPIgnition switch ON or engine running Displays temperature of inside of
EPS control unit (
°C or °F)
ASSIST LEVEL Engine running
100 %
*3
VEHICLE SPEEDVehicle stopped
0 km/h or mph
While driving Approximately equal to the indication
on speedometer*4
(inside of ±
10%)
WARNING LAMP EPS warning lamp: ON
On
EPS warning lamp: OFF Off
ENGINE STATUS Engine not running
Stop
Engine running Run
Revision: August 2015 2016 Versa Note
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STC-18
< DTC/CIRCUIT DIAGNOSIS >
C1601 BATTERY POWER SUPPLY
DTC/CIRCUIT DIAGNOSIS
C1601 BATTERY POWER SUPPLY
DTC LogicINFOID:0000000012431953
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”
Is DTC
“C1601” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-18, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431954
Regarding Wiring Diagram information, refer to STC-11, "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 contro l 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 PO WER SUPPLY CIRCUIT (1)
1. Check voltage between EPS control unit harness connector terminal and ground.
DTC Display item Malfunction detected condition Possible cause
C1601 BATTERY VOLT When a power supply voltage to the EPS control unit
is maintained at 17.5 V or more or at less than 9V
continuously for five second or more. • Harness or connector
• EPS control unit
•Fuse
• Power supply system
•Battery
EPS control unit
—Con tin uit y
Connector Terminal
E23 18Ground Yes
Revision: August 2015 2016 Versa Note
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C1604 TORQUE SENSORSTC-21
< DTC/CIRCUIT DIAGNOSIS >
C
DE
F
H I
J
K L
M A
B
STC
N
O P
C1604 TORQUE SENSOR
DTC LogicINFOID:0000000012431955
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1604” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-21, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431956
Regarding Wiring Diagram information, refer to STC-11, "Wiring Diagram".
1.CHECK TORQUE SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF to ON. CAUTION:
Never start the engine.
2. Check voltage between EPS control unit harness connector terminal and ground.
CAUTION:
Steering wheel in neutral position . (There is no steering force.)
Is the inspection result normal?
YES >> GO TO 2.
NO >> Perform the trouble diagnosis for battery power supply circuit. Refer to STC-18, "
Diagnosis Proce-
dure".
2.CHECK TORQUE SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between EPS control unit harness connector terminal and ground. CAUTION:
Steering wheel in neutral position . (There is no steering force.)
DTCDisplay item Malfunction detected condition Possible cause
C1604 TORQUE SENSOR When torque sensor output signal is malfunctioning. • Harness or connector
• Torque sensor
• EPS control unit
EPS control unit
—Vo l ta g e
(Approx.)
Connector Terminal
M54 13Ground 5 V
Revision: August 2015 2016 Versa Note
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C1606 EPS MOTORSTC-23
< DTC/CIRCUIT DIAGNOSIS >
C
DE
F
H I
J
K L
M A
B
STC
N
O P
C1606 EPS MOTOR
DTC LogicINFOID:0000000012431957
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1606” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-23, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431958
1.CHECK EPS MOTOR
Check the EPS motor. Refer to STC-23, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO >> EPS motor is malfunction. Replace steering column assembly. Refer to ST-9, "
Exploded View".
2.CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect EPS motor 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-37, "Removal and Installation".
NO >> Repair or replace malfunctioning component.
Component Inspection INFOID:0000000012431959
1.CHECK EPS MOTOR
1. Turn the ignition switch OFF.
2. Disconnect EPS motor harness connector.
3. Check resistance between EPS motor connector terminals.
Is the inspection result normal?
DTC Display item Malfunction detected condition Possible cause
C1606 EPS MOTOR When the motor driver malfunction of EPS control
unit or EPS motor malfunction is detected. • Harness or connector
• EPS motor
• EPS control unit
EPS motor
Resistance (Approx.)
Te r m i n a l
19 200.1 Ω or less
Revision: August 2015 2016 Versa Note
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C1607, C1608 EPS CONTROL UNIT
STC-25
< DTC/CIRCUIT DIAGNOSIS >
C
D E
F
H I
J
K L
M A
B
STC
N
O P
C1607, C1608 EPS CONTROL UNIT
DTC LogicINFOID:0000000012431960
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1607” or “C1608” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-25, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431961
1.PERFORM SELF-DIAGNOSIS
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Erase “Self Diagnostic Result” of “EPS”.
3. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1607” or “C1608” detected?
YES >> Replace EPS control unit. Refer to STC-37, "Removal and Installation".
NO >> Check EPS control unit pin terminals for damage or loose connection with harness connector. If
any item are damaged, repair or replace malfunctioning component.
DTC Display item Malfunction detected condition Possible cause
C1607 EEPROM When the memory (EEPROM)
system malfunction is
detected in EPS control unit.
EPS control unit
C1608 CONTROL UNIT When the internal malfunction is detected in EPS
control unit.
Revision: August 2015
2016 Versa Note
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STC-26
< DTC/CIRCUIT DIAGNOSIS >
C1609 VEHICLE SPEED SIGNAL
C1609 VEHICLE SPEED SIGNAL
DescriptionINFOID:0000000012431962
EPS control unit receives the vehicle speed signal from ABS actuator and electric unit (control unit) via CAN
communication line.
DTC LogicINFOID:0000000012431963
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”
Is DTC
“C1609” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-26, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431964
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF DIAGNOSTIC RESULT
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “ABS”.
Is any DTC detected?
YES >> Check the DTC.
NO >> GO TO 2.
2.PERFORM SELF DIAGNOSTIC RESULT
With CONSULT
Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1609” detected?
YES >> Replace EPS control unit. Refer to STC-37, "Removal and Installation".
NO >> Check EPS control unit pin terminals for damage or loose connection with harness connector. If any item are damaged, repair or replace malfunctioning component.
DTC Display item Malfunction detected condition Possible cause
C1609 CAN VHCL SPEED • Malfunction is detected in vehicle speed signal that
is output from ABS actuator and electric unit (con-
trol unit) via CAN communication.
• ABS actuator and electric unit (control unit) input signal error is detected. • Harness or connector
• CAN communication line
• EPS control unit
• ABS malfunction
- Vehicle speed signal error
Revision: August 2015
2016 Versa Note
cardiagn.com

C1610 ENGINE STATUS SIGNALSTC-27
< DTC/CIRCUIT DIAGNOSIS >
C
DE
F
H I
J
K L
M A
B
STC
N
O P
C1610 ENGINE STATUS SIGNAL
DescriptionINFOID:0000000012431965
EPS control unit receives the engine status signal from ECM via CAN communication line.
DTC LogicINFOID:0000000012431966
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1610” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-27, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431967
1.PERFORM ECM SELF DIAGNOSTIC RESULT
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “ENGINE”. Refer to EC-60, "
CONSULT Function".
Is any DTC detected?
YES >> Check the DTC. Refer to EC-87, "DTCIndex".
NO >> GO TO 2.
2.PERFORM SELF DIAGNOSTIC RESULT
With CONSULT
Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“C1610” detected?
YES >> Replace EPS control unit. Refer to STC-37, "Removal and Installation".
NO >> Check EPS control unit pin terminals for damage or loose connection with harness connector. If
any item are damaged, repair or replace malfunctioning components.
DTC Display item Malfunction detected condition Possible cause
C1610 CAN ENG RPM • Malfunction is detected in engine status signal
that is output from ECM via CAN communica-
tion.
• ECM input signal error is detected. • Harness or connector
• CAN communication line
• EPS control unit
•ECM
- Engine status signal error
Revision: August 2015
2016 Versa Note
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STC-28
< DTC/CIRCUIT DIAGNOSIS >
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000012431968
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CA N communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit communicate data but selectively reads required data only.
DTC LogicINFOID:0000000012431969
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If “DTC CONFIRMATION PROCEDURE” has been previously conducted, always turn ignition switch OFF and
wait at least 10 seconds before conducting the next test.
>> GO TO 2.
2.DTC REPRODUCTION PROCEDURE
With CONSULT
1. Turn the ignition switch OFF to ON.
2. Perform “Self Diagnostic Result” of “EPS”.
Is DTC
“U1000” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-28, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000012431970
Proceed to LAN-16, "Trouble Diagnosis Flow Chart".
DTC Display item Malfunction detected condition Possible cause
U1000 CAN COMM CIRCUIT EPS control unit is not transmitting/re-
ceiving CAN communication signal for 2
seconds or more.• CAN communication error
• EPS control unit
Revision: August 2015
2016 Versa Note
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