2007 NISSAN TIIDA EC Engine Control System

DIAGNOSIS SYSTEM (EPS CONTROL UNIT)
STC-7
< FUNCTION DIAGNOSIS >[EPS]
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DIAGNOSIS SYSTEM (EPS CONTROL UNIT)
CONSULT-III Function (EPS)INFOID:0000000001697722
FUNCTION
CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.
SELF-DIAG RESULTS MODE
Display Item List
CAUTION:
If “CAN COMM CIRCUIT [U1000]” is displayed with other DTCs, first perform the trouble diagnosis for CAN communication
line.
How to Erase Self-Diagnostic Results
1. Perform applicable inspection of malfunctioning item and then repair or replace.
2. Turn ignition switch “OFF” to erase memory.
3. Turn ignition switch “ON” and select “SELF-DIAG RESULTS” mode with CONSULT-III.
4. Touch “ERASE” on CONSULT-III screen to erase DTC memory.
CAUTION:
If memory cannot be erased, perform diagnosis.
DATA MONITOR
Display Item List
EPS diagnostic mode Description
SELF-DIAG RESULTS  Displays EPS self-diagnosis results.
DATA MONITOR  Displays EPS input/output data in real time.
CAN DIAG SUPPORT MNTR  The result of transmit/receive diagnosis of CAN communication can be read.
ECU PART NUMBER  EPS control unit part number can be read.
Item
(CONSULT-III screen terms)Diagnostic item is detected when.... Check item
BATTERY VOLT
[C1601]When the power supply malfunction supplied to EPS control unit is
detected.STC-9
TORQUE SENSOR
[C1604]When the torque sensor malfunction assembled in steering column
assembly is detected. STC-11
EPS MOTOR
[C1606]When the motor driver malfunction of EPS control unit or EPS motor
malfunction is detected.STC-13
EEPROM
[C1607]When the memory (EEPROM) system malfunction is detected in
EPS control unit.STC-15
CONTROL UNIT
[C1608]When the internal malfunction is detected in EPS control unit.STC-16
CAN VHCL SPEED
[C1609]When the malfunction is detected in vehicle speed signal received
with CAN communication.STC-17
CAN ENG RPM
[C1610]When the malfunction is detected in engine status signal received
with CAN communication.STC-19
CAN COMM CIRCUIT
[U1000]When EPS control unit is not transmitting or receiving CAN commu-
nication signal 2 seconds or more.STC-21
NO DTC IS DETECTED.
FURTHER TESTING MAY BE RE-
QUIRED.No NG item has been detected. —

STC-8
< FUNCTION DIAGNOSIS >[EPS]
DIAGNOSIS SYSTEM (EPS CONTROL UNIT)
EPS CONTROL UNIT PART NUMBER
Display a part number of EPS control unit carried by a vehicle.
Monitor item (Unit) Remarks
MOTOR VOL (V) Power supply voltage for EPS control unit is displayed
TORQUE SENSOR (Nm) Steering wheel turning force detected by torque sensor is displayed
MOTOR SIG (A) Current commanded value to EPS motor is displayed
MOTOR CURRENT (A) Current value consumed by EPS motor is displayed
VEHICLE SPEED (km/h) or (mph) Vehicle speed is displayed from vehicle speed signal with CAN communication
WARNING LAMP (ON/OFF) EPS warning lamp control status is displayed
DERATING STAT (ON/OFF) Protect overload status is displayed
ENGINE STATUS (STOP/RUN) Engine speed is displayed from engine status signal with CAN communication

C1607 EEPROM
STC-15
< COMPONENT DIAGNOSIS >[EPS]
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C1607 EEPROM
DescriptionINFOID:0000000001716742
EPS control unit incorporates a memory function.
DTC LogicINFOID:0000000001716743
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to STC-15, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000001697727
1.PERFORM SELF-DIAGNOSIS
With CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “EPS” with CONSULT-III.
3. Touch “ERASE”.
4. Turn ignition switch OFF, and wait at least 10 seconds.
5. Start engine.
6. Perform the self-diagnosis again.
Is the
“EEPROM [C1607]” displayed?
YES >> Replace EPS control unit. Refer to ST-9, "Removal and Installation".
NO >>INSPECTION END
Special Repair Requirement (Models with ESP)INFOID:0000000001730966
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform the neutral position adjustment for the steering angle sensor, when replacing the EPS control
unit. Refer to BRC-90, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION : Descrip-
tion".
>> END
DTC Display item Malfunction detected condition Possible cause
C1607 EEPROMWhen the memory (EEPROM) system malfunction is
detected in EPS control unit. Harness or connector
 EPS control unit
Self-diagnosis results
EEPROM

C1610 CAN ENG RPM
STC-19
< COMPONENT DIAGNOSIS >[EPS]
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C1610 CAN ENG RPM
DescriptionINFOID:0000000001716753
EPS control unit receives engine RPM input from the ECM through the CAN communication lines.
DTC LogicINFOID:0000000001716754
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to STC-19, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000001697730
1.CHECK DTC WITH ECM
Perform self-diagnosis for ECM. Refer to EC-107, "
CONSULT-III Function" (HR16DE with EURO-OBD), EC-
462, "CONSULT-III Function" (HR16DE without EURO-OBD), EC-772, "CONSULT-III Function" (MR18DE),
EC-1104, "
Diagnosis Description" (K9K).
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
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
Va l u e".
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.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >>INSPECTION END
NG >> Perform self-diagnosis for ECM. Refer to EC-107, "
CONSULT-III Function" (HR16DE with EURO-
OBD), EC-462, "
CONSULT-III Function" (HR16DE without EURO-OBD), EC-772, "CONSULT-III
Function" (MR18DE), EC-1104, "Diagnosis Description" (K9K).
Special Repair Requirement (Models with ESP)INFOID:0000000001730969
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
DTC Display item Malfunction detected condition Possible cause
C1610 CAN ENG RPMWhen the malfunction is detected in engine status
signal received with CAN communication. Harness or connector
 CAN communication line
 EPS control unit
Self-diagnosis results
CAN ENG RPM

U1000 CAN COMM CIRCUIT
STC-21
< COMPONENT DIAGNOSIS >[EPS]
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U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000001716748
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 CAN 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 transmits/receives data but selectively reads required data only.
DTC LogicINFOID:0000000001716749
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to STC-21, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000001697731
1.CHECK CAN COMMUNICATION CIRCUIT
With CONSULT-III
1. Turn ignition switch ON and start engine.
2. Select “SELF-DIAG RESULTS” mode for “EPS” with CONSULT-III.
3. Perform the self-diagnosis.
Is the
“CAN COMM CIRCUIT [U1000]” displayed?
YES >> Print out CONSULT-II screen and go to LAN-30, "CAN System Specification Chart".
NO >>INSPECTION END
Special Repair Requirement (Models with ESP)INFOID:0000000001730970
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform the neutral position adjustment for the steering angle sensor, when replacing the EPS control
unit. Refer to BRC-90, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION : Descrip-
tion".
>> END
DTC Display item Malfunction detected condition Possible cause
U1000 CAN COMM CIRCUITWhen EPS control unit is not transmitting or receiving
CAN communication signal for 2 seconds or more. Harness or connector
 CAN communication line
 EPS control unit
Self-diagnosis results
CAN COMM CIRCUIT

EPS SYSTEM SYMPTOMS
STC-29
< SYMPTOM DIAGNOSIS >[EPS]
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SYMPTOM DIAGNOSIS
EPS SYSTEM SYMPTOMS
Symptom ChartINFOID: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: ONCAN communication line
STC-30
Combination meter
EPS warning lamp does not turn OFF for sev-
eral seconds after starting the engineEngine runningCAN 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 turningCAN 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 turningWheel alignment
STC-34
Steering wheel turning force
(Mechanical malfunction)
Unbalance steering wheel turning force,
while driving (Torque variation) While driving
 Steering wheel turningSteering column intermediate
shaft installation condition
STC-35
Steering wheel turning force
(Mechanical malfunction)

EPS WARNING LAMP DOES NOT TURN OFF
STC-31
< SYMPTOM DIAGNOSIS >[EPS]
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EPS WARNING LAMP DOES NOT TURN OFF
Diagnosis ProcedureINFOID:0000000001697734
SYMPTOM:
EPS warning lamp does not turn OFF for several seconds after starting the engine.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to STC-7, "
CONSULT-III Function (EPS)".
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
2.CHECK EPS CONTROL UNIT POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EPS control unit harness connector.
3. Turn ignition switch ON. (Do not start engine.)
4. Check voltage between EPS control unit harness connector
M53 (A) terminal 10 and M54 (B) terminal 17 and ground.
5. Turn ignition switch OFF.
6. Check voltage between EPS control unit harness connector
M53 (A) terminal 10 and M54 (B) terminal 17 and ground.
7. Connect EPS control unit harness connector.
OK or NG
OK >> GO TO 3.
NG >> Check the following. If any items are damaged, repair
or replace damaged parts.
 60 A fusible link (letter m , located in the fuse and fusible link box).
 10 A fuse [No. 2, located in the fuse block (J/B)].
 Harness for short or open between battery and EPS control unit harness connector M54 termi-
nal 17.
 Harness for short or open between ignition switch and EPS control unit harness connector M53
terminal 10.
3.CHECK EPS CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EPS control unit harness connector.
Connector Terminal Voltage
(A) M53 10 – Ground Battery voltage
(B) M54 17 – Ground Battery voltage
AWGIA0031ZZ
Connector Terminal Voltage
(A) M53 10 – Ground Approx. 0 V
(B) M54 17 – Ground Battery voltage
AWGIA0028ZZ

STEERING WHEEL TURNING FORCE IS HEAVY OR LIGHT
STC-33
< SYMPTOM DIAGNOSIS >[EPS]
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STEERING WHEEL TURNING FORCE IS HEAVY OR LIGHT
Diagnosis ProcedureINFOID:0000000001697735
SYMPTOM:
Steering wheel turning force is heavy or light, while driving.
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 VEHICLE SPEED SIGNAL
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-25, "
CONSULT-III
Function (ABS)" (with ABS) or BRC-105, "CONSULT-III Function (ABS)" (with ESP).
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 3.
3.CHECK COMBINATION METER SIGNAL
Perform self-diagnosis with combination meter. Refer to MWI-22, "
CONSULT-III Function (METER/M&A)".
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
4.CHECK ENGINE STATUS SIGNAL
Perform self-diagnosis for ECM. Refer to EC-107, "
CONSULT-III Function" (HR16DE with EURO-OBD), EC-
462, "CONSULT-III Function" (HR16DE without EURO-OBD), EC-772, "CONSULT-III Function" (MR18DE),
EC-1104, "
Diagnosis Description" (K9K).
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 5.
5.CHECK EPS MOTOR SYSTEM
Perform trouble diagnosis for EPS motor. Refer to STC-13, "
Diagnosis Procedure".
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6.CHECK EPS CONTROL UNIT
Check EPS control unit input/output signal. Refer to STC-22, "
EPS Control Unit Input/Output Signal Reference
Va l u e".
OK or NG
OK >> GO TO 7.
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.
7.SYMPTOM CHECK
Check again.
OK or NG
OK >>INSPECTION END
NG >> Check the steering wheel turning force because there may be mechanical malfunction. Refer to
ST-6, "
On-Vehicle Inspection and Service".