control unit INFINITI M35 2007 Factory Service Manual

STC-10
[EPS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
3. CHECK POWER STEERING CONTROL UNIT POWER SUPPLY CIRCUIT
Turn ignition switch ON, and then check voltage between power
steering control unit harness connector M8 and ground.
OK or NG
OK >> Power supply and ground circuit are normal.
NG >> Power supply circuit open or shorted. Repair or replace
any inoperative parts.
Symptom: The Steering Force Does Not Change Smoothly According to the
Vehicle Speed
NGS000E4
Heavy steering force with the static steering/light steering force during high-speed driving
1. POWER STEERING SOLENOID VALVE SIGNAL INSPECTION 1
1. Start engine.
2. Change the vehicle speed from 0 to 100 km/h (0 to 62 MPH)
slowly, and then check voltage between power steering control
unit harness connector M8 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 7.
2. POWER STEERING SOLENOID VALVE SIGNAL INSPECTION 2
1. Activate fail-safe function by running the engine speed at 1,500 rpm or higher for 10 seconds with the
vehicle stopped.
2. Change the engine speed to the idling, to approximately 1,600
rpm, and to approximately 3,000 rpm slowly, and then check
voltage between power steering control unit harness connector
M8 and ground.
OK or NG
OK >> GO TO 3.
NG >> GO TO 8.
3. CHECK POWER STEERING SOLENOID VALVE CONNECTOR
Turn ignition switch OFF, disconnect power steering solenoid valve harness connector, and check terminal for
deformation, disconnection, looseness, etc.
OK or NG
OK >> GO TO 4.
NG >> Harness or connector open or shorted. Repair or replace any inoperative parts.Terminal 1 – ground : Battery voltage (Approx. 12 V)
SGIA1232E
Terminal 7 – ground : The voltage has changed from
approximately 4.4 - 6.6 V to
approximately 2.4 - 3.6 V
SGIA1233E
Terminal 7 – ground : The voltage has changed from
approximately 5.5 V to approxi-
mately 2.1 V step-by-step.
SGIA1233E

TROUBLE DIAGNOSIS
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[EPS]
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STC
Revision: 2007 April2007 M35/M45
4. CHECK POWER STEERING SOLENOID VALVE POWER SUPPLY CIRCUIT
Check continuity between power steering control unit harness con-
nector M8 and power steering solenoid valve harness connector F25
(VQ35DE), E211 (VK45DE).
OK or NG
OK >> GO TO 5.
NG >> Open or short in harness. Repair or replace any inoper-
ative parts.
5. CHECK POWER STEERING SOLENOID VALVE GROUND CIRCUIT
Check continuity between power steering solenoid valve harness
connector F25 (VQ35DE), E211 (VK45DE) and ground.
OK or NG
OK >> GO TO 6.
NG >> Open or short in harness. Repair or replace any inoper-
ative parts.
6. CHECK POWER STEERING SOLENOID VALVE
Apply voltage power steering solenoid valve connector, and then
make sure that the operating sound (clicking sound) is heard.
OK or NG
OK >> Perform steering wheel turning force inspection. Refer
to PS-10, "
CHECKING STEERING WHEEL TURNING
FORCE" .
NG >> Power steering solenoid valve is inoperative. Replace.
Power steering control unit Power steering solenoid valve Continuity
Terminal 7 Terminal 1 Yes
SGIA1235E
Terminal 2 – Ground : Continuity exist.
SGIA1236E
Terminal 1 (+) - 2 (–) : Operating sound is heard.
SGIA1284E

STC-12
[EPS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
7. CHECK VEHICLE SPEED SIGNAL CIRCUIT
Change the vehicle speed, and then check voltage waveform
between power steering control unit harness connector M8 and
ground.
OK or NG
OK >> Power steering control unit is inoperative. Replace it.
NG >> Check the following systems and replace if necessary.

Harness between unified meter & A/C amp and power steering control unit.

Unified meter & A/C amp and vehicle speed signal circuit Refer to DI-28, "UNIFIED METER
AND A/C AMP" .
8. CHECK ENGINE SPEED SIGNAL CIRCUIT
Warm up the engine, and then check voltage waveform between
power steering control unit harness connector M8 and ground when
the engine speed is the idling and at approximately 2,000 rpm.
OK or NG
OK >> Power steering control unit is inoperating. Replace it.
NG >> Check the following systems and replace if malfunction is detected.

Harness between ECM and power steering control unit

ECM engine speed signal circuit. Refer to EC-826, "CONSULT-II Function (ENGINE)" .
Terminal 3 – GroundRepeat Approx. 0 V and approx. 5 V
SGIA1237EELF1080D
Terminal 5 – GroundAt Idle
Approx. 2,000 rpmSGIA1289EPBIA3654J
PBIA3655J

STC-16
[RAS]
SYSTEM DESCRIPTION
Revision: 2007 April2007 M35/M45
SYSTEM DESCRIPTIONPFP:00000
ComponentsNGS000E8
RAS (Rear Active Steer) FunctionNGS000E9
A. RAS control unit B. Model following control C. Target vehicle dynamics model
D. Rear wheel steering angle com-
mand value operationE. Rear wheel steering angle servo F. Vehicle speed signal (CAN)
G. Steering angle signal (CAN) H. Vehicle speed sensor I. Steering angle sensor
J. RAS actuator assembly
SGIA1241E
Part name Function
RAS control unit

Calculate the vehicle speed signal from CAN communication and the signals from steering
angle sensor and rear wheel steering angle sensor by a computer, and then control the rear
wheel steering angle.

Fail-safe function is activated when the electrical system is malfunctioning. The output signal
to the actuator is turned OFF during this mode. At that time, the RAS warning lamp illumi-
nates and indicates the system is malfunctioning.

It performs the communication control function with other control units via CAN communica-
tion.

This enables system diagnosis with CONSULT-II.
RAS actuatorThe efficiency of the rear wheel steer improves by locating the electric motor actuator into the
lower link of rear suspension.
Steering angle sensor

Measure the steering angle and send it to RAS control unit via CAN communication.

It is shared with the steering angle sensor for VDC.
Rear wheel steering angle sensor

It sends the rear wheel steering angle status to RAS control unit. The accuracy of rear wheel
steer improves by comparing the vehicle speed signal from CAN communication with the
rear wheel steering angle target value calculated from the wheel angle sensor signal, and it
controls them.

There are 2 types of rear wheel steering angle sensors (main/sub). If one of them is malfunc-
tioning, the other operates the fail-safe mode and stops the control.
RAS warning lamp

It turns on when the fail-safe function is operated and indicates that a RAS control malfunc-
tion has occurred.

It turns on when ignition switch turns on and turns off after the engine is started.

It indicates the suspect system by blinking when performing the self-diagnosis (without CON-
SULT-II).

TROUBLE DIAGNOSIS
STC-19
[RAS]
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Revision: 2007 April2007 M35/M45
Component Parts LocationNGS000EC
A. RAS warning lamp B. Steering angle sensor C. RAS control unit
D. RAS motor relay E. RAS motor F. Rear wheel steering angle sensor
G. Noise suppressor
SGIA1053J

STC-26
[RAS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
Control Unit Input/Output Signal StandardNGS000EF
CIRCUIT TESTER REFERENCE VALUE
CAUTION:
When checked using a circuit tester for voltage measurement, connector terminals should not be
forcefully extended.
Terminal
Measuring point Measuring condition Standard
+
(wire color)–
1 (L) — CAN-H —
4 (G)
GroundRR MAIN SIG Neutral Approx. 2.4 V
5 (W) RR VCCIgnition switch ON Approx. 5 V
Ignition switch OFF Approx. 0 V
7 (R) RR SUB SIG Neutral Approx. 2.4 V
8 (P) — CAN-L —
15 (B/W)
GroundRR SEN GND — Continuity exit
22 (P/L) STOP/L SWBrake pedal depressed Battery voltage (Approx. 12 V)
Brake pedal not depressed Approx. 0 V
25 (L/W) RLYIgnition switch ON Battery voltage (Approx. 12 V)
Ignition switch OFF Approx. 0 V
26 (G/W) WARNON Approx. 1.4 V or less
OFF Ignition voltage: 2.8 V or more
27 (G/B) IGNIgnition switch ON Battery voltage (Approx. 12 V)
Ignition switch OFF Approx. 0 V
34 (B) GND — Continuity exit
36 (LG) P/S SOLNormal (Vehicle speed)0 km/h (0 MPH) Approx. 4.4 - 6.6 V
100 km/h (62 MPH) Approx. 2.4 - 3.6 V
In fail-safe mode
(Engine speed)0 - 1,500 rpm Approx. 4.4 - 6.6 V
1,500 - 3,000 rpm Approx. 3.5 V
3,000 rpm or more Approx. 2.1 V
37 (L/Y) MOTOR VCCIgnition switch ON Battery voltage (Approx. 12 V)
Ignition switch OFF Approx. 0 V
38 (W) MTR-1 (RH) —
39 (B) MTR-2 (LH) —
40 (B/W) MOTOR GND — Continuity exit

TROUBLE DIAGNOSIS
STC-27
[RAS]
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Revision: 2007 April2007 M35/M45
STANDARD BY CONSULT-II
CAUTION:
The output signal indicates the RAS control unit calculation data. The normal values will be displayed
even in the event that the output circuit (harness) is open.
CONSULT-II Function (RAS/HICAS)NGS000EG
FUNCTION
CONSULT-II can display each self-diagnostic item using the diagnostic test modes shown following.
Monitor item Condition Reference values
VHCL SPEED SE [km/h] or [mph] Ignition switch ON or engine running Almost in accordance with the speedome-
ter display. It is not a malfunction, through
it might not be corresponding just after
ignition switch is turned ON.
STEERING ANG [°]Turning steering wheel clockwise or coun-
terclockwise.Displays the angle when the steering
wheel turns from the neutral position
ENGINE SPEED [rpm] Engine runningAlmost in accordance with tachometer dis-
play
POWER STR SOL [A]Accelerate the vehicle from 0 to 100 km/h
(0 to 62 MPH)0 km/h (0 MPH): Approx. 1.10 A
100 km/h (62 MPH): Approx. 0.54 A
RR ST ANG-MAI [V]
Perform the ACTIVE TEST and stroke the
actuator (with tires off the ground)Neutral: Approx. 2.4 V
Turn steering wheel to right for full stroke:
Approx. 4.4 V
Turn steering wheel to left for full stroke:
Approx. 0.4 V RR ST ANG-SUB [V]
RR ST ANG-VOL [V]
Ignition switch ON or engine runningApprox. 5 V
C/U VOLTAGE [V]Battery voltage (Approx. 12 V)
MOTOR VOLTAGE [V] Battery voltage (Approx. 12V)
MOTOR CURRENT [A]Perform the ACTIVE TEST and stroke the
actuator.It is normal when there is the current out-
put at stroke
MTR CRNT OPE [A]Turning steering wheel clockwise or coun-
terclockwise while ignition switch is ON or
running the engineNeutral (Steering force is zero and straight-
ahead position): Approx. 0 A
The value is changed according to steering
left or right
RR ANGLE OPE [°]RAS actuator assembly turned full right Approx. 1°
RAS actuator assembly neutral Approx. 0°
RAS actuator assembly turned full left Approx. - 1°
STOP LAMP SW [ON/OFF] Depressing or releasing brake pedalBrake pedal depressed: ON
Brake pedal not depressed: OFF
HICAS RELAY [ON/OFF]
Ignition switch ON or engine runningIgnition switch ON: ON
FAIL SAFE [ON/OFF] Not activated
WARNING LAMP (ON/OFF)RAS warning lamp ON: ON
RAS warning lamp OFF: OFF
Diagnostic test mode Function Reference page
SELF-DIAG RESULTSReceives self-diagnosis results from RAS control unit and
indicates DTCs.STC-28, "
SELF-DIAG
RESULT MODE"
DATA MONITORReceives input/output signals from RAS control unit and
indicates and stores them to facilitate locating cause of mal-
functions.STC-30, "DATA MONI-
TOR MODE"
CAN DIAG SUPPORT MNTRMonitors transmitting/receiving status of CAN communica-
tion.LAN-44, "CAN Diagnos-
tic Support Monitor"
ACTIVE TESTSends command to RAS actuator to change output signals
and check operation of output system.STC-30, "ACTIVE TEST
MODE"
ECU PART NUMBER Displays RAS control unit part number.STC-30, "RAS CONTROL
UNIT PART NUMBER"

STC-28
[RAS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
CONSULT-II SETTING PROCEDURE
Refer to GI-38, "CONSULT-II Start Procedure" .
SELF-DIAG RESULT MODE
Operation Procedure
1. Perform “CONSULT-II Start Procedure”. Refer to GI-38, "CONSULT-II Start Procedure" .
2. Touch “PRINT” to print out the self-diagnostic results if necessary. Check RAS warning lamp if “NO FAIL-
URE” is displayed.
3. Perform the appropriate inspection from the display item list, and repair or replace the malfunctioning
component. Refer to STC-28, "
Display Item List" .
Display Item List
CAUTION:
When malfunctions are detected in several systems, including the “CAN COMM [U1000]” and “CON-
TROL UNIT (CAN) [U1010]”, inspect the CAN communication system.
DTC Diagnostic item Diagnostic item is detected when... Check items
C1923 STEERING ANGLE SEN [NO CHANGE]While driving at 60 km/h (37 MPH)
or more, steering angle does not
change for a while.STC-39
C1924 STEERING ANGLE SEN [NO NEUT STATE]When driving some distance, no
neutral signal (ON signal) is input.STC-39
C1915 RR ST ANGLE SENSOR [MAIN SIGNAL]The main sensor input signal is
malfunctioning for some time
against the sensor power supply
value.STC-40
C1916 RR ST ANGLE SENSOR [SUB SIGNAL]When the main sensor input signal
is 2.4 - 2.6 V, the sub sensor input
signal is malfunctioning for some
time compared to the sensor power
supply value.STC-40
C1917 RR ST ANGLE SENSOR [OFFSET SIG1] An excessive difference has
occurred in the input values of main
sensor and sub sensor.STC-40
C1918 RR ST ANGLE SENSOR [OFFSET SIG2]
C1914 RR ST ANGLE SENSOR [ABNORMAL VOL]Higher or lower value compared to
the standard voltage.STC-40
C1921 MOTOR OUTPUTNo engine speed is input for a cer-
tain time.STC-44
C1911 MOTOR VOLTAGE [LOW VOLTAGE]The motor power supply voltage is
lower than ignition power supply
voltage with RAS motor relay ON.STC-35
C1912 MOTOR VOLTAGE [BAD OBSTRCT]The motor power supply voltage is
inputting for some time with motor
power supply OFF by RAS control
unit.STC-35
C1913 MOTOR OUTPUT [ABNORMAL SIG]When the motor current value is 10
A or more, actual output is exces-
sively low and the condition contin-
ues for some time.STC-37
C1902 MOTOR OUTPUT [REV CURRENT]The current flows in the opposite
direction when the motor current is
output. STC-37
C1903 MOTOR OUTPUT [NO CURRENT]The current flows when the motor
current is not output. STC-37
C1904 MOTOR OUTPUT [OVERCURRENT]The excessive high current flows
when the motor current is output.STC-37

TROUBLE DIAGNOSIS
STC-29
[RAS]
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Revision: 2007 April2007 M35/M45
How to Erase Self-Diagnostic Results
1. Perform applicable inspection of malfunctioning item and then repair or replace.
2. Start engine, and touch “START (NISSAN BASED VHCL)” “RAS/HICAS” “SELF-DIAG RESULTS” and
“ERASE” in this order to erase the diagnostic memory.
CAUTION:
If memory cannot be erased, repeat step 1, 2.
3. Perform self-diagnosis again, and make sure that DTC memory is erased.
C1910 MOTOR OUTPUT [MOTOR LOCK]When 17 A or more current flows to
the motor, the rear wheel steering
angle sensor signal does not
change for some time.STC-37
C1919 VEHICLE SPEED SEN [NO SIGNAL]No vehicle speed signal is input for
some time.STC-38
C1900 CONTROL UNIT [ABNORMAL1]
Control unit malfunctionSTC-35
C1901 CONTROL UNIT [ABNORMAL2]
C1905 CONTROL UNIT [ABNORMAL3]
C1906 CONTROL UNIT [ABNORMAL5]
C1907 CONTROL UNIT [ABNORMAL4]
C1908 CONTROL UNIT [ABNORMAL7]
C1909 CONTROL UNIT [ABNORMAL6]
C1922 CONTROL UNIT [ABNORMAL8]
C1927 CONTROL UNIT [ABNORMAL5]
C1928 CONTROL UNIT [ABNORMAL9]
C1920 STEERING ANGLE SEN [NO SIGNAL]No steering angle signal is input for
some time.STC-39
C1926 STEERING ANGLE SEN

An unexpected signal is input.

Steering angle sensor outputs the
malfunction signal.STC-39
C1929 VDCABS actuator and electric unit (con-
trol unit) outputs the malfunction
signal.STC-43
U1000 CAN COMM CIRCUITWhen a RAS control unit is not
transmitting or receiving CAN com-
munication signal 2 seconds or
more.STC-44
U1010 CONTROL UNIT (CAN)When detecting error during the ini-
tial diagnosis of CAN controller of
RAS control unit.STC-44
DTC Diagnostic item Diagnostic item is detected when... Check items

STC-30
[RAS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
DATA MONITOR MODE
Operation Procedure
1. Perform “CONSULT-II Start Procedure”. Refer to GI-38, "CONSULT-II Start Procedure" .
2. Touch “DATA MONITOR”.
3. Select from “SELECT MONITOR ITEM”, screen of data monitor is displayed.
NOTE:
When malfunction is detected, CONSULT-II performs REAL-TIME DIAGNOSIS. Also, any malfunction
detected while in this mode will be displayed in real time.
Display Item List
ACTIVE TEST MODE
Operation Procedure
1. Perform “CONSULT-II Start Procedure”. Refer to GI-38, "CONSULT-II Start Procedure" .
2. When turning the steering wheel right or left, the rear wheel turns in the same direction. If the steering
wheel is not turned, the rear wheel turns left and right 5 times.
RAS CONTROL UNIT PART NUMBER
1. Perform “CONSULT-II Start Procedure”. Refer to GI-38, "CONSULT-II Start Procedure" .
2. The part number described on RAS control unit sticker is displayed.
Item [Display or Unit] Remarks
VHCL SPEED SE [km/h] or [mph] Vehicle speed received via CAN communication is displayed.
STEERING ANG [°] Steering angle received via CAN communication is displayed.
ENGINE SPEED [rpm] Engine speed received via CAN communication is displayed.
POWER STR SOL [A]Power steering solenoid controlling current that RAS control unit
outputs is displayed.
RR ST ANG-MAI [V]Rear wheel steering angle main sensor output voltage is dis-
played.
RR ST ANG-SUB [V] Rear wheel steering angle sub sensor output voltage is displayed.
RR ST ANG VOL [V]Voltage supplied from RAS control unit to rear wheel steering
angle sensor is displayed.
C/U VOLTAGE [V] Voltage supplied to RAS control unit is displayed.
MOTOR VOLTAGE [V] Voltage supplied from RAS control unit to RAS motor is displayed.
MOTOR CURRENT [A]RAS motor relay controlling current that RAS control unit outputs
is displayed.
MOTOR CRNT OPE [A] Current commanded value to RAS motor is displayed.
RR ANG OPE [°]Angle commanded value to rear wheel steering angle sensor is
displayed.
STOP LAMP SW [ON/OFF] Condition of stop lamp switch ON/OFF is displayed.
HICAS RELAY [ON/OFF] RAS motor relay ON/OFF condition is displayed.
FAILSAFE [ON/OFF] Fail-safe ON/OFF condition is displayed.
WARNING LAMP [ON/OFF] RAS warning lamp operating condition is displayed.
STEERING ANG RR ST ANG MAI RR ST ANG SUB MOTOR CURRENT
0° (Neutral) 2.4 V 2.4 V No output (Approx. 0 A)
R 90°Approx. 4.4 V Approx. 4.4 V
Output (change)
L 90°Approx. 0.4 V Approx. 0.4 V