2010 NISSAN LATIO steering

SRS-50
< ON-VEHICLE REPAIR >
COLLISION DIAGNOSIS
For Side and Ro llover Collision
INFOID:0000000005716112
FOR SIDE AND ROLLOVER COLLISION: Wh en SRS is activated in a collision
CAUTION:
Due to varying models and option levels, not all part s listed in the chart below apply to all vehicles.
WORK PROCEDURE
1. Before performing any of the following steps, ensure that all vehicle body and structural repairs have been
completed.
2. Replace the following components:
- Front seat back assembly (on the side on which side air bag is activated).
- Door finisher (on the side on which door-mounted curtain air bag is activated).
- Pop-up roll bar assemblies and pop-up roll bar covers.
- Side air bag (satellite) sensor LH/RH (on the side on which side air bag is activated).
- Diagnosis sensor unit.
- Seat belt pre-tensioner assemblies.
3. Check the SRS components and the related parts using the following table. Replace any SRS components and the related parts showing visible signs of damage (dents, cracks,
deformation, etc.).
4. Perform self-diagnosis using CONSULT-III and “AIR BAG” warning lamp. Refer to SRS-19, "
SRS Opera-
tion Check" for details. Make sure entire SRS operates properly.
5. After the work is completed, perform self-diagnosis to check that no malfunction is detected. Refer to SRS-18, "
Self-Diagnosis Function (Without CONSULT-III)".
SRS INSPECTION (FOR SIDE AND ROLLOVER COLLISION)
Diagnosis sensor unit If none of the SRS components have been activated:
1. Check case for dents, cracks or deformities.
2. Check connectors for damage, and terminals for deformities.
3. If no damage is found, reinstall with new fasteners.
4. If damaged—REPLACE. Install diagnosis sensor unit with new fasteners.
Steering wheel 1. Visually check steering wheel for deformities.
2. Check harness (built into steering wheel) and connectors for damage, and terminals for defor- mities.
3. Install driver air bag module into the steering wheel to check fit and alignment with the wheel.
4. Check steering wheel for excessive free play.
5. If no damage is found, reinstall.
6. If damaged—REPLACE.
Spiral cable If the driver front air bag has not deployed:
1. Visually check spiral cable and combination switch for damage.
2. Check connectors and protective tape for damage.
3. Check steering wheel for noise, binding or heavy operation.
4. If no damage is found, reinstall.
5. If damaged—REPLACE.
Occupant classification system
(Passenger seat) 1. Remove passenger seat assembly.
2. Check control unit case for dents, cracks of deformities.
3. Check connectors and pressure sensor tube for damage, and terminals for deformities.
4. Check seat frame and cushion pan for dents or deformities.
5. If no damage is found, reinstall seat with new fasteners.
6. If damaged — REPLACE seat cushion assembly with new fasteners.
Harness and connectors 1. Check connectors for poor connection, damage, and terminals for deformities.
2. Check harness for binding, chafing, cuts, or deformities.
3. If no damage is found, reinstall the harness and connectors.
4. If damaged—REPLACE the damaged harness. Do not attempt to repair, splice or modify any
SRS harness.
Instrument panel assembly If the passenger front air bag has NOT deployed: 1. Visually check instrument panel for damage.
2. If no damage is found, reinstall the instrument panel assembly.
3. If damaged—REPLACE the instrument panel assembly.
Part
Inspection
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STEERING
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CONTENTS
STEERING CONTROL SYSTEM
EPS
BASIC INSPECTION ....... .............................
3
DIAGNOSIS AND REPAIR WORKFLOW ..... .....3
Work Flow ........................................................... ......3
SYSTEM DESCRIPTION ..............................5
EPS SYSTEM ... .............................................. .....5
System Diagram .................................................. ......5
System Description ...................................................5
Component Parts Location ........................................6
Component Description .............................................6
DIAGNOSIS SYSTEM (EPS CONTROL UNIT)
.....
8
CONSULT-III Function ........................................ ......8
DTC/CIRCUIT DIAGNOSIS ..........................9
C1601 BATTERY POWER SUPPLY ..................9
Description .......................................................... ......9
DTC Logic .................................................................9
Diagnosis Procedure .................................................9
C1604 TORQUE SENSOR .................................11
Description ..............................................................11
DTC Logic ...............................................................11
Diagnosis Procedure ...............................................11
C1606 EPS MOTOR ...........................................13
Description .......................................................... ....13
DTC Logic ...............................................................13
Diagnosis Procedure ...............................................13
Component Inspection ............................................13
C1607, C1608 EPS CONTROL UNIT ................15
Description .......................................................... ....15
DTC Logic ...............................................................15
Diagnosis Procedure ...............................................15
C1609 VEHICLE SPEED SIGNAL .....................16
Description ........................................................... ....16
DTC Logic ................................................................16
Diagnosis Procedure ...............................................16
C1610 ENGINE STATUS SIGNAL ...................17
Description ...............................................................17
DTC Logic ................................................................17
Diagnosis Procedure ...............................................17
U1000 CAN COMM CIRCUIT ...........................18
Description ...............................................................18
DTC Logic ................................................................18
Diagnosis Procedure ...............................................18
EPS WARNING LAMP ......................................19
Description ...............................................................19
Component Function Check ....................................19
Diagnosis Procedure ...............................................19
ECU DIAGNOSIS INFORMATION ..............20
EPS CONTROL UNIT .......................................20
Reference Value .................................................. ....20
Wiring Diagram - ELECTRONICALLY CON-
TROLLED POWER STEERING SYSTEM - ............
22
Fail-Safe .............................................................. ....23
DTC Inspection Priority Chart ..................................24
DTC Index ...............................................................24
SYMPTOM DIAGNOSIS ..............................25
EPS WARNING LAMP DOES NOT TURN ON ...25
Description ........................................................... ....25
Diagnosis Procedure ...............................................25
EPS WARNING LAMP DOES NOT TURN
OFF ....................................................................
26
Description ...............................................................26
Diagnosis Procedure ...............................................26
STEERING WHEEL TURNING FORCE IS
HEAVY OR LIGHT ............................................
27
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STC-2
Description ..............................................................27
Diagnosis Procedure ..............................................27
UNBALANCE STEERING WHEEL TURNING
FORCE AND RETURN BETWEEN RIGHT
AND LEFT ..........................................................
28
Description ..............................................................28
Diagnosis Procedure ..............................................28
UNBALANCE STEERING WHEEL TURNING
FORCE (TORQUE VARIATION) .......................
29
Description ........................................................... ...29
Diagnosis Procedure ............................................ ...29
PRECAUTION ............................................30
PRECAUTIONS .............................................. ...30
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
30
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ..................................
30
Service Notice or Precaution for EPS System ........31
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EPS SYSTEMSTC-5
< SYSTEM DESCRIPTION > [EPS]
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SYSTEM DESCRIPTION
EPS SYSTEM
System DiagramINFOID:0000000005600156
System DescriptionINFOID:0000000005600157
• 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 mo tor while extremely using the power steering func-
tion (e.g., full steering) consecutively for protec ting EPS motor and EPS control unit (Overload protection
control). While activating overload protection control, the assist torque gradually decreases, and the steering
wheel turning force becomes heavy. The normal assist torque reactivates by no steering.
• In case of an error in the electrical system, the fail- safe function stops output signals to the EPS motor. Then
the previous state is changed to the manual steering state.
• Self-diagnosis can be done with CONSULT-III.
• EPS control unit will decrease assistance under the following 2 conditions.
- Extensive steering at low speed will cause the ECU and MOTOR to heat up, once temperature reaches crit-
ical point ECU will reduce current to reduce heat up. System will recover as temperature lowers (reduced or
no assistance).
- Holding steering on rack-end (full lock) for 1 second will cause the system to engage rack-end protection. This reduces assistance down to 50% in order to prevent heat up. Assistance is immediately returned to
100% when steering released or turned away from rack-end.
- Communicates the signal from each control unit via CAN communication.
WGIA0187E
Control unit Signal status
ECM Transmits mainly the follow
ing signals to EPS control uni t via CAN communication.
Engine status signal
ABS actuator and electric unit
(control unit) Transmits mainly the follow
ing signals to EPS control uni t via CAN communication.
Vehicle speed signal
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STC-8
< SYSTEM DESCRIPTION >[EPS]
DIAGNOSIS SYSTEM (EPS CONTROL UNIT)
DIAGNOSIS SYSTEM
(EPS CONTROL UNIT)
CONSULT-III FunctionINFOID:0000000005600160
FUNCTION
CONSULT-III can display each diagnostic item us ing the diagnostic test modes shown following.
ECU IDENTIFICATION
Displays the part number stored in the control unit.
SELF-DIAG RESULTS MODE
Display Item List
Refer to STC-24, "DTC Index".
CAUTION:
If “CAN COMM CIRCUIT [U1000]” is disp layed with other DTCs, first perform the trouble diagnosis for
CAN communication line.
DATA MONITOR MODE
Display Item List
*1: Almost in accordance with the value of MOTOR SIG. It is not a malfunction though these values are not accorded when steerin g
quickly.
*2: It is not a malfunction, though it might not be corresponding just after ignition switch in turned ON. Diagnostic test mode
Function
ECU identification Steering column assembly number can be read.
Self diagnostic result Self-diagnostic results can be read and erased quickly.
Data monitor Input/Output data in the EPS control unit can be read.
Monitor item (Unit) Remarks
MOTOR VOL (V) Displays the power supply voltage for EPS control unit.
TORQUE SENSOR (Nm) Displays steering wheel turning force detected by torque sensor.
MOTOR CURRENT (A) Displays the current value consumed by EPS motor.
MOTOR SIG (A)
*1Displays the current commanded value to EPS motor.
DERATING STAT (ON/OFF%) Protect overload status is displayed.
VEHICLE SPEED (km/h) or (MPH)
*2Vehicle speed is displayed from vehicle speed signal via CAN communication.
WARNING LAMP (On/Off) EPS warning lamp control status is displayed.
ENGINE STATUS (Stop/Run) Engine speed is displayed from engine status signal via CAN communication.
Revision: January 20102010 Versa

STC-10
< DTC/CIRCUIT DIAGNOSIS >[EPS]
C1601 BATTERY POWER SUPPLY
Is the inspection result normal?
YES >> GO TO 3.
NO >> Check the following. If any items are damaged, repair or replace damaged parts.
• 10A fuse (#2) open
- Harness for short between 10A fuse (#2) and pow er steering control unit harness connector No.
10 terminal.
• 60A fusible link (M) open
- Harness for short between 60A fusible link (M) and power steering control unit harness connec-
tor No. 10 terminal.
• Harness for open between ignition switch and power steering control unit harness connector No. 17 terminal.
• Harness for open between battery and power steering control unit harness connector No. 17 ter-
minal.
• Battery or ignition switch.
3.CHECK BATTERY VOLTAGE SIGNAL (1)
With CONSULT-III
1. Connect EPS control unit harness connector.
2. Start the engine. CAUTION:
Stop the vehicle.
3. Select “EPS”, “DATA MONITOR” and “MOTOR VO LT”, and perform the battery voltage inspection.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace EPS control unit. Refer to PS-9, "
Removal and Installation".
4.CHECK MOTOR VOLTAGE SIGNAL (2)
With CONSULT-III
Select “MOTOR VOLT” in “DATA MONITOR” of the EPS control unit. Check motor voltage with the steering
wheel fully turned leftward or rightward.
Is the value in
“DATA MONITOR”“between 9 V and 17.5 V”?
YES >> Check pin terminal and connection of each harness connector for damage or loose connection.
NO >> Check battery power supply and ignition power supply. Refer to STC-22, "
Wiring Diagram - ELEC-
TRONICALLY CONTROLLED POWER STEERING SYSTEM -".
EPS control unit
—Volt a ge
Connector Terminal
M53 10
Ground Battery voltage
M54 17
Monitor item ConditionDisplay value
MOTOR VOLT Engine runningBattery voltage
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C1604 TORQUE SENSORSTC-11
< DTC/CIRCUIT DIAGNOSIS > [EPS]
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C1604 TORQUE SENSOR
DescriptionINFOID:0000000005600165
Torque sensor detects the steering torque, and transmit the signal to EPS control unit.
DTC LogicINFOID:0000000005600166
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Turn the ignition switch OFF to ON.
2. Perform EPS control unit self-diagnosis.
Is DTC
“C1604” detected?
YES >> Proceed to diagnosis procedure. Refer to STC-11, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000005600167
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 terminals and ground. CAUTION:
Steering wheel is 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-9, "
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 is neutral position. (There is no steering force.)
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit or short to ground or short to power in harness or connectors.
DTC Display 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
—Volt a g e
Connector Terminal
M53 5Ground Approx. 5 V
EPS control unit
—Con tin uit y
Connector Terminal
M53 7Ground Yes
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STC-12
< DTC/CIRCUIT DIAGNOSIS >[EPS]
C1604 TORQUE SENSOR
3.CHECK TORQUE SENSOR SIGNAL
1. Turn ignition switch ON.
2. Check voltage between EPS control unit harness connector terminal and ground. CAUTION:
Steering wheel is neutral position . (There is no steering force.)
Is the inspection result normal?
YES >> GO TO 4.
NO >> Torque sensor is malfunction. Replac e steering column assembly. Refer to PS-9, "
Removal and
Installation".
4.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 PS-9, "Removal and Installation".
NO >> Repair or replace error-detected parts.
EPS control unit —Volt a ge
Connector Terminal
M53 4
Ground Approx. 2.5V
6
Revision: January 20102010 Versa