19, " SRS Operation Check " .
WHEN SRS IS ACTIVATED IN THE SIDE OR ROLLOVER COLLISION
1. Replace the following components:
- Front seat back assembly (on the side on which side air bag is activated)
- Diagnosis sensor unit
- (LH or RH) side air bag (satellite) sensor (on the side on which side air bag is activated)
2. 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).
3. Conduct self-diagnosis using CONSULT-III and “AIR BAG” warning lamp. Refer to SRS-19, " SRS Opera-
tion Check " for details. Ensure entire SRS operates properly.
WHEN SRS IS NOT ACTIVATED IN THE SIDE OR ROLLOVER COLLISION
1. Check the SRS components and the related parts using the following table.
- If the front seat back assembly is damaged, t he front seat back assembly must be replaced.
2. Conduct self-diagnosis using CONSULT-III and “AIR BAG” warning lamp. Refer to SRS-19, " SRS Opera-
tion Check " for details. Ensure entire SRS operates properly.
SRS INSPECTION (FOR SIDE AND ROLLOVER COLLISION) Steering wheel 1. Visually check steering wheel for deformities.
2. Check harness (built into steering wheel) and connectors for damage, and terminals for deformities.
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 deployed:
REPLACE the 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 classifica-
tion system (Passen-
ger seat) 1. Remove passenger seat.
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 connec-
tors 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 har- ness.
Instrument panel If the passenger front air bag has deployed:
REPLACE the instru-
ment 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.
3. If damaged—REPLACE the instrument panel.
Part SRS is activated SRS is NOT activated
STC
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CONTENTS
STEERING CONTROL SYSTEM
EPS
SERVICE INFORMATION .. ..........................
2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary fo r Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Service Notice or Precau tion for EPS System ..........3
EPS SYSTEM ... .............................................. .....4
System Description ............................................. ......4
Schematic ........................................................... ......5
CAN Communication ........................................... ......5
TROUBLE DIAGNOSIS ................................. .....6
Fail-Safe Function ............................................... ......6
How to Perform Trouble Diagnosis ..................... ......6
Component Parts Location .................................. ......7
Wiring Diagram - EPS - ... ..........................................8
EPS Control Unit Input/O utput Signal Reference
Value ................................................................... ......
9 EPS Terminal and Reference Value ....................
....10
CONSULT-III Function ( EPS) ..................................11
Symptom Chart .................................................... ....13
TROUBLE DIAGNOSIS FOR SYSTEM ............ 14
DTC C1601 BATTERY VOLT .............................. ....14
DTC C1604 TORQUE SENSOR ......................... ....15
DTC C1606 EPS MOTOR ................................... ....16
DTC C1607 EEPROM ......................................... ....17
DTC C1608 CONTROL UNIT .............................. ....17
DTC C1609 CAN VHCL SPEED ......................... ....18
DTC C1610 CAN ENG RPM ............................... ....19
DTC U1000 CAN COMM CIRCUIT ..................... ....19
Component Inspection ......................................... ....19
TROUBLE DIAGNOSIS FOR SYMPTOMS ...... 21
EPS Warning Lamp Does Not Turn ON ..................21
EPS Warning Lamp Does Not Turn OFF ................21
Steering Wheel Turning Force Is Heavy or Light . ....22
Unbalance Steering Wheel Turning Force and Re-
turn Between Right and Left ................................ ....
23
Unbalance Steering Wheel Turning Force (Torque
Variation) ............................................................. ....
24
PRECAUTIONS
STC-3
< SERVICE INFORMATION >
[EPS] C
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5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Service Notice or Precaution for EPS System INFOID:0000000004307286
CAUTION:
Check or confirm the following item wh en performing the trouble diagnosis.
• Check any possible causes by interviewing the symptom and it’s condition from the customer if any
malfunction, such as EPS warn ing lamp turns ON, occurs.
• Check if air pressure and size of tires are proper, the specified part is used for the steering wheel,
and control unit is genuine part.
• Check if the connection of steer ing 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 alignmen t is adjusted properly.
• Check if there is any damage or modification to su spension 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 disconnect ing the EPS control unit har-
ness connector, turn ignition switch “OFF” and disconnect
battery ground cable. Because battery voltage is applied to
EPS control unit even if igniti on switch is turned “OFF”.
• When connecting or disconnect ing 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.
• Before replacing EPS control unit, perform EPS control unit input/output signal inspectio n and make sure whether EPS
control unit functions properly or not. Refer to STC-9, " EPS
Control Unit Input/Output Signal Reference Value " . SEF289H
SEF291H
SDIA1848E
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Schematic
INFOID:0000000004307288
COMPONENTS FUNCTION DESCRIPTION
CAN Communication INFOID:0000000004307289
SYSTEM DESCRIPTION CAN (Controller Area Network) is a serial communication li ne 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.
For details, refer to LAN-26, " CAN System Specification Chart " .
STC-6< SERVICE INFORMATION >
[EPS]
TROUBLE DIAGNOSIS
TROUBLE DIAGNOSIS
Fail-Safe Function INFOID:0000000004307290
• 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 steer ing state. (Control turning force steering wheel
becomes heavy.)
How to Perform Trouble Diagnosis INFOID:0000000004307291
BASIC CONCEPT
• To perform trouble diagnosis, it is a must to have an understanding about vehicle systems (control and mechanism) thoroughly.
• It is also important to clarify customer complaints before starting
the inspection.
First of all, reproduce the symptoms, and understand them fully.
Ask customer about his/her complaints carefully. In some cases, it
will be necessary to check symptoms by driving vehicle with cus-
tomer.
CAUTION:
Customers are not professionals. It is dangerous to make an
easy guess like “maybe the customer means that...” or
“maybe the customer mentions this symptom”.
• It is essential to check symptoms right from the beginning in order to repair malfunctions completely.
For intermittent malfunctions, reproduce symptoms based on inter-
view with customer and past examples. Do not perform inspection
on ad hoc basis. Most intermittent malfunctions are caused by
poor contacts. In this case, it will be effective to shake suspected
harness or connector by hand. When repairing without any symp-
tom diagnosis, you cannot judge if malfunctions has actually been
eliminated.
PRECAUTIONS FOR TROUBLE DIAGNOSIS
• Be sure to check the procedures of the trouble diagnosis in advance. Refer to "How to Perform Trouble Diagnosis" .
• Always erase memory after completing trouble diagnosis. Refer to STC-11, " CONSULT-III Function (EPS) " .
• Checking continuity and voltage between units, be sure to check connector terminals for disconnection,
looseness, bend, or collapse. Repair or replace app licable part if any non-standard condition is detected.
• Be careful not to forcibly extend any connector terminal if a circuit tester is used for the check.
• Always confirm the general precautions. Refer to GI-3, " General Precaution " .
INTERVIEW
• Complaints vary depending on the person. It is important to clarify the customer's actual remarks.
• Ask the customer about what sy mptoms occur under what condi-
tions. Use the information to reproduce the symptom of confirm by
vehicle. SEF233G
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EPS Control Unit Input/Output Signal Reference Value INFOID:0000000004307294
SPECIFICATIONS WITH CONSULT-III CAUTION:
The output signal indicates the EPS control unit calculation date. The normal values will be displayed
even in the event that the output circuit (harness) is open. B
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Data are reference values and are
measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection , be sure not to extend forcibly any connector terminals.
CONSULT-III Function (EPS) INFOID:0000000004307296
FUNCTION CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.
SELF-DIAG RESULTS MODE
Display Item List Terminal
Wire
color Item Condition Data (Approx.)
4 V Torque sensor sub Engine running Steering wheel: Not steering
(There in no steering force) 2.5 V
Steering wheel: Steering 1.7 V – 3.3 V
(The value is changed accord- ing to steering left or right)
5 BR Torque sensor power supply Ignition switch: ON 8 V
Ignition switch: OFF 0 V
6 G Torque sensor main Engine running Steering wheel: Not steering
(There is no steering force) 2.5 V
Steering wheel: Steering 1.7 V – 3.3 V
(The value is changed accord- ing to steering left or right)
7 R Torque sensor ground Always 0 V
9 L CAN-H — —
10 O Power supply Ignition switch: ON Battery voltage
Ignition switch: OFF 0 V
16 P CAN-L — —
17 R Power supply (Memory back-up) Ignition switch: ON Battery voltage
Ignition switch: OFF Battery voltage
18 B Ground Always 0 V
19 — Motor (+) — —
20 — Motor (–) — — Diagnostic test mode Function Reference page
Self-diagnostic results • Self-diagnostic results can be read and erased quickly. "SELF-DIAG
RESULTS MODE"
Data monitor • Inpu t/Output data in the EPS control unit can be read. "DATA MONI-
TOR"
CAN diagnostic support monitor • The results of transmit/receive diagnosis of CAN communication can be read. LAN-8ECU part number • EPS control unit
part number can be read. "EPS CON-
TROL UNIT
PART NUM- BER"
DTC C1601
BATTERY VOLT "
TORQUE SENSOR
[C1604] When the torque sensor malfunction assembled in steering column
assembly is detected. STC-15, " DTC C1604
TORQUE SENSOR "
EPS MOTOR
[C1606] When the motor driver
malfunction of EPS control unit or EPS motor
malfunction is detected. STC-16, " DTC C1606
EPS MOTOR "
EEPROM
[C1607] When the memory (EEPROM) system malfunction is detected in
EPS control unit. STC-17, " DTC C1607
EEPROM "
CONTROL UNIT
[C1608] When the internal malfunction is detected in EPS control unit. STC-17, " DTC C1608
CONTROL UNIT "
CAN VHCL SPEED
[C1609] When the malfunction is detected in vehicle speed signal received
with CAN communication. STC-18, " DTC C1609
CAN VHCL SPEED "
CAN ENG RPM
[C1610] When the malfunction is detected in engine status signal received
with CAN communication. STC-19, " DTC C1610
CAN ENG RPM "
CAN COMM CIRCUIT
[U1000] When EPS control unit is
not transmitting or receiving CAN commu-
nication signal 2 seconds or more. STC-19, " DTC U1000
CAN COMM CIRCUIT "
NO DTC IS DETECTED.
FURTHER TESTING MAY BE RE-
QUIRED. No NG item has been detected. —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 cons umed 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 la mp control status is displayed
DERATING STAT (ON/OFF) Protect overload status is displayed
ENGINE STATUS (STOP/RUN) Engine spee d is displayed from engine status signal with CAN communication