2007 INFINITI M35 power steering

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
STC-11
[EPS]
C
D
E
F
H
I
J
K
L
MA
B
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

TROUBLE DIAGNOSIS
STC-27
[RAS]
C
D
E
F
H
I
J
K
L
MA
B
STC
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

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

TROUBLE DIAGNOSIS
STC-31
[RAS]
C
D
E
F
H
I
J
K
L
MA
B
STC
Revision: 2007 April2007 M35/M45
Diagnosis Procedure with Self-Diagnosis Function (Without CONSULT-II)NGS000EL
DESCRIPTION
If a malfunction is detected in the system, the RAS warning lamp turns on and indicates the malfunction. At
that time, fail-safe activates, and then stops the function.
SELF-DIAGNOSIS PROCEDURE
1. Start engine.
2. Turn steering wheel left and right at 20° or more and 5 times or more within 10 seconds. And then depress
the service brake 5 times or more.
3. RAS warning lamp blinks (displays normal/malfunction).
SELF-DIAGNOSIS DISPLAY
RAS warning lamp blinks and displays the self-diagnostic results.

Only DTCs are displayed as the pattern shown in the figure, and
then repeat the display.

If all items are normal, RAS warning lamp blinks at 4 Hz cycle.
SELF-DIAGNOSIS DISPLAY ITEMS
HOW TO ERASE SELF-DIAGNOSIS
If there is the history data for when the fail-safe has activated in the past, erase the memory with CONSULT-II.
Refer to STC-29, "
How to Erase Self-Diagnostic Results" .
CAN CommunicationNGS000EM
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. Refer to LAN-50, "
CAN Sys-
tem Specification Chart" .
SGIA1243E
DTC (warning lamp blinks) Diagnosis item Inspection item
11 RAS control unitSTC-35, "
Inspection 1: RAS Control Unit Malfunction"
12 Motor power supplySTC-35, "Inspection 2: Motor Power Supply System"
13 Motor outputSTC-37, "Inspection 3: RAS Motor Output Malfunction"
21 Vehicle speed signalSTC-38, "Inspection 4: Vehicle Speed Signal"
22 Steering angle signalSTC-39, "Inspection 5: Steering Angle Signal Malfunction"
24 Rear wheel steering angle (main)STC-40, "Inspection 6: Rear Main Signal and Rear Sub Signal
Malfunction"
25 Rear wheel steering angle (sub)STC-40, "Inspection 6: Rear Main Signal and Rear Sub Signal
Malfunction"
26 VDCSTC-43, "Inspection 7: VDC Malfunction"
33 Engine speed signalSTC-44, "Inspection 8: Engine Speed Signal Malfunction"

STC-32
[RAS]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
For Fast and Accurate Trouble DiagnosisNGS000EN
Check the following items with the vehicle stopped

Is air pressure and size of tires proper?

Is the specified part used for the steering wheel?

Is control unit a genuine part?

Are there any fluid leakage from steering gear assembly, power steering oil pump, and hydraulic pipes,
etc? Refer to PS-8, "
Checking Fluid Leakage" .

Is the fluid level proper? Refer to PS-8, "Checking Fluid Level" .

Is the wheel alignment is adjusted properly? Refer to FSU-6, "Wheel Alignment Inspection" (2WD), FSU-
24, "Wheel Alignment Inspection" (AWD).

Are there any damage or modification to suspension or body resulting in increased weight or altered
ground clearance?

Check each link installation condition of suspension and axle.

Is the battery voltage proper?

Check each connector connection condition.
Check the following items while driving the vehicle

Conditions when the error occurred (5W 1H).

Is the engine is normal?
Basic InspectionNGS000EO
BASIC INSPECTION 1: POWER SUPPLY CIRCUIT TERMINAL LOOSENESS AND BATTERY
Check battery terminals for looseness on both positive and negative ones and ground connection. Also make
sure that battery voltage does not drop.
BASIC INSPECTION 2: RAS WARNING LAMP INSPECTION
1. Make sure RAS warning lamp turns on when ignition switch is turned ON.

If it does not turn on, refer to STC-33, "Trouble Diagnosis Chart" .
2. Make sure that RAS warning lamp turns off when the engine is started after ignition switch is turned ON. If
it does not turn off, perform self-diagnosis. Refer to STC-28, "
SELF-DIAG RESULT MODE" .
3. Always erase DTC memory after completing self-diagnosis. Refer to STC-29, "
How to Erase Self-Diag-
nostic Results" .
BASIC INSPECTION 3: RAS CONTROL UNIT POWER SUPPLY CIRCUIT AND GROUND CIR-
CUIT INSPECTION
1. CHECK RAS CONTROL UNIT CONNECTOR
Turn ignition switch OFF, disconnect RAS control unit harness connector, and check terminal for deformation,
disconnection, looseness, etc.
OK or NG
OK >> GO TO 2.
NG >> Poor connection of connector terminal. Repair or replace the terminal.
2. CHECK RAS CONTROL UNIT GROUND CIRCUIT
1. Disconnect RAS control unit harness connector B476, and then
check continuity between RAS control unit harness connector
B476 and ground.
OK or NG
OK >> GO TO 3.
NG >> Ground circuit open or shorted. Repair or replace any
inoperative parts. Terminal 34 – Ground : Continuity should exit.
SGIA1244E