Brake Control System: Other Nissan Note E12

Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER"

The Supplemental Restraint System such as "AIR BAG" and "SEAT BELT PRE- TENSIONER", used along with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of collision. Information necessary to service the system safely is included in the " SRS AIRBAG " and " SEAT BELTS SRS AIRBAG " articles of this Service Information.

PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS

Precaution for Brake System

Scheme 30

1. Brake fluid use refer to " «RECOMMENDED FLUIDS AND LUBRICANTS»(ref-675584-S23480474382014120500000) ".
2. Do not reuse drained brake fluid.
3. Do not spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it off immediately and wash with water if it gets on a painted surface.
4. Always confirm the specified tightening torque when installing the brake pipes.
5. After pressing the brake pedal more deeply or harder than normal driving, such as air bleeding, check each item of brake pedal. Adjust brake pedal if it is outside the standard value.
6. Do not use mineral oils such as gasoline or light oil to clean. They may damage rubber parts and cause improper operation.
7. Always loosen the brake tube flare nut with a flare nut wrench.
8. Tighten the brake tube flare nut to the specified torque with a crowfoot (A) and torque wrench (B).
9. Always connect the battery terminal when moving the vehicle.
10. Turn the ignition switch OFF and disconnect the ABS actuator and electric unit (control unit) harness connector or the battery negative terminal before performing the work.
11. Check that no brake fluid leakage is present after replacing the parts.

1. Just after starting vehicle after ignition switch is ON, brake pedal may vibrate or motor operating noise may be heard from engine compartment. This is a normal condition.
2. When an error is indicated by ABS or another warning lamp, collect all necessary information from customer (what symptoms are present under what conditions) and check for simple causes before starting diagnostic servicing. Besides electrical system inspection, check brake booster operation, brake fluid level and oil leaks.
3. If tire size and type are used in an improper combination or brake pads are not Genuine NISSAN parts, stopping distance or steering stability may deteriorate.
4. ABS might be out of order or malfunctions by putting a radio (wiring inclusive), an antenna and a lead-in wire near the control unit.
5. If aftermarket parts (car stereo, CD player, etc.) have been installed, check for incidents such as harness pinches, open circuits, and improper wiring.
6. VDC system may not operate normally or a VDC OFF indicator lamp or SLIP indicator lamp may light. When replacing the following parts with parts other than genuine parts or making modifications: Suspension-related parts (shock absorber, spring, bushing, etc.), tires, wheels (other than specified sizes), brake-related parts (pad, rotor, caliper, etc.), engine-related parts (muffler, ECM, etc.) and body reinforcement-related parts (roll bar, tower bar, etc.). When driving with worn or deteriorated suspension, tires and brake-related parts.

Scheme 31

Scheme 32

1. Solder the repair part, and wrap it with tape. [Twisted wire fray must be 110 mm (4.33 in) or less.]
2. Do not bypass the repair point with wire. (If it is bypassed, the turnout point cannot be separated and the twisted wire characteristics are lost.)

Special Service Tool

The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.

Tool number (Kent-Moore No.) Tool name Description KV991J0080 (J-45741) ABS active wheel sensor tester Checking operation of ABS active wheel sensors

Scheme 33

Commercial Service Tool

Tool name Description Flare nut crowfoot Torque wrench Removing and installing brake piping 10 mm (0.39 in)/12 mm (0.47 in) Power Tool Loosening nuts, screws and bolts

Scheme 34

Scheme 35

ABS Actuator and Electric Unit (Control Unit)

Electric unit (control unit) is integrated with actuator and comprehensively controls VDC function, TCS function, ABS function and EBD function.

ELECTRIC UNIT (CONTROL UNIT)

1. Brake fluid pressure is controlled according to signals from each sensor.
2. If malfunction is detected, the system enters fail-safe mode.

ACTUATOR

The following components are integrated with ABS actuator.

Pump

Returns the brake fluid reserved in reservoir to master cylinder by reducing pressure.

Motor

Activates the pump according to signals from ABS actuator and electric unit (control unit).

Motor Relay

Operates the motor ON/OFF according to signals from ABS actuator and electric unit (control unit).

Actuator Relay (Main Relay)

Operates each valve ON/OFF according to signals from ABS actuator and electric unit (control unit).

ABS IN Valve

Switches the fluid pressure line to increase or hold according to signals from control unit.

ABS OUT Valve

Switches the fluid pressure line to increase, hold or decrease according to signals from control unit.

Cut Valve 1, Cut Valve 2

Shuts off the ordinary brake line from master cylinder, when VDC function and TCS function are activated.

Suction Valve 1, Suction Valve 2

Supplies the brake fluid from master cylinder to the pump, when VDC function and TCS function are activated.

Return Check Valve

Returns the brake fluid from brake caliper and wheel cylinder to master cylinder by bypassing orifice of each valve when brake is released.

Reservoir

Temporarily reserves the brake fluid drained from brake caliper, so that pressure efficiently decreases when decreasing pressure of brake caliper and wheel cylinder.

Yaw rate/side/decel G sensor

Calculates the following information that affects the vehicle, and transmits a signal to ABS actuator and electric unit (control unit) via communication lines.

1. Vehicle rotation angular velocity (yaw rate signal)
2. Vehicle lateral acceleration (side G signal) and longitudinal acceleration (decel G signal)

Pressure Sensor

Detects the brake fluid pressure and transmits signal to ABS actuator and electric unit (control unit).

Wheel Sensor and Sensor Rotor

Note. Wheel sensor of front wheel is installed on steering knuckle. Sensor rotor of front wheel is integrated in wheel hub assembly. Wheel sensor of rear wheel is installed on back plate of rear brake. Sensor rotor of rear wheel is installed on rear brake drum. Never measure resistance and voltage value using a tester because sensor is active sensor. Downsize and weight reduction is aimed. IC for detection portion and magnet for sensor rotor are adopted. Power supply is supplied to detection portion so that magnetic field line is read. Magnetic field that is detected is converted to current signal. When sensor rotor rotates, magnetic field changes. Magnetic field change is converted to current signals (rectangular wave) and is transmitted to ABS actuator and electric unit (control unit). Change of magnetic field is proportional to wheel speed.

Scheme 36

Stop Lamp Switch

Detects the operation status of brake pedal and transmits converted electric signal to ABS actuator and electric unit (control unit).

Steering Angle Sensor

Detects the following information and transmits steering angle signal to ABS actuator and electric unit (control unit) via CAN communication.

1. Steering wheel rotation amount
2. Steering wheel rotation angular velocity
3. Steering wheel rotation direction

VDC OFF Switch

1. Non-operational status or standby status of VDC and TCS functions can be selected using VDC OFF switch. VDC OFF indicator lamp indicates the operation status of function. (ON: Non-operational status, OFF: Standby status)
2. VDC OFF indicator lamp turns OFF (standby status) when the engine is started again after it is stopped once while VDC OFF indicator lamp is ON (non-operational status).

Parking Brake Switch

Detects the operation status of parking brake switch and transmits converted electric signal from combination meter to ABS actuator and electric unit (control unit) via CAN communication.

Scheme 37

INPUT SIGNAL AND OUTPUT SIGNAL

Major signal transmission between each unit via communication lines is shown in the following table.

CONDITIONS FOR INDICATOR LAMP ILLUMINATION

1. Turns ON when VDC and TCS functions are switched to non-operational status (OFF) by VDC OFF switch.
2. Turns ON when ignition switch turns ON and turns OFF when the system is normal, for bulb check purposes.

CONDITIONS FOR WARNING LAMP ILLUMINATION

Turns ON when ignition switch turns ON and turns OFF when the system is normal, for bulb check purposes.

Scheme 38

Scheme 39

1. Side slip or tail slip may occur while driving on a slippery road or intending an urgent evasive driving maneuver. VDC function detects side slip status using each sensor when side slip or tail slip is about to occur and improves vehicle stability by brake control and engine output control during driving.
2. In addition to ABS function, EBD function and TCS function, target side slip amount is calculated according to steering operation amount from steering angle sensor. By comparing this information with vehicle side slip amount that is calculated from information from yaw rate/side G sensor and wheel sensor, vehicle driving conditions (conditions of understeer or oversteer) are judged and vehicle stability is improved by brake force control on all 4 wheels and engine output control.
3. VDC function can be switched to non-operational status (OFF) by operating VDC OFF switch. In this case, VDC OFF indicator lamp turns ON.
4. Control unit portion automatically improves driving stability by performing brake force control as well as engine output control, by transmitting drive signal to actuator portion according to difference between target side slip amount and vehicle side slip amount
5. Brake force control function at braking hard detects driver's brake operations with the pressure sensor, judges a brake booster's maximum brake power function by using information from the vacuum sensor, and enhances more powerful braking force by controlling brakes of four wheels.
6. VDC warning lamp blinks while VDC function is in operation and indicates to the driver that the function is in operation.
7. CONSULT can be used to diagnose the system.
8. Fail-safe function is adopted. When a malfunction occurs in VDC function, the control is suspended for VDC function and TCS function. However, ABS function and EBD function operate normally. Refer to " «FAIL-SAFE»(ref-675599-S06844757042014120500000) ".

Major signal transmission between each unit via communication lines is shown in the following table.

Major signal transmission between each unit via communication lines is shown in the following table.

Scheme 40

Scheme 41

1. By preventing wheel lock through brake force (brake fluid pressure) control that is electronically controlled by detecting wheel speed during braking, stability during emergency braking is improved so that obstacles can be easily bypassed by steering operation.
2. During braking, control units calculate wheel speed and pseudo-vehicle speed, and transmit pressure increase, hold or decrease signals to actuator portion according to wheel slip status.
3. The following effects are obtained by preventing wheel lock during braking. Vehicle tail slip is prevented during braking when driving straight. Understeer and oversteer tendencies are moderated during braking while cornering. Obstacles may be easily bypassed by steering operation during braking.
4. CONSULT can be used to diagnose the system.
5. Fail-safe function is adopted. When a malfunction occurs in ABS function, the control is suspended for VDC function, TCS function and ABS function. However, EBD function operates normally. Refer to " «VDC/TCS/ABS: FAIL-SAFE»(ref-675599-S07759118342014120500000) ".

Major signal transmission between each unit via communication lines is shown in the following table.

Scheme 42

Scheme 43

1. By preventing rear wheel slip increase through rear wheel brake force (brake fluid pressure) control that is electronically controlled when slight skip on front and rear wheels are detected during braking, stability during braking is improved.
2. EBD function is expanded and developed from conventional ABS function and corrects rear wheel brake force to appropriate level by electronic control according to load weight (number of passengers).
3. During braking, control unit portion compares slight slip on front and rear wheels by wheel speed sensor signal, transmits drive signal to actuator portion when rear wheel slip exceeds front wheel slip for the specified value or more, and controls rear wheel brake force (brake fluid pressure) so that increase of rear wheel slip is prevented and slips on front wheel and rear wheel are nearly equalized. ABS control is applied when slip on each wheel increases and wheel speed is the threshold value of ABS control or less.
4. CONSULT can be used to diagnose the system.
5. Fail-safe function is adopted. When a malfunction occurs in EBD function, the control is suspended for VDC function, TCS function, ABS function and EBD function. Refer to " «VDC/TCS/ABS: FAIL-SAFE»(ref-675599-S07759118342014120500000) ".

Major signal transmission between each unit via communication lines is shown in the following table.

VDC AND TCS FUNCTIONS

VDC warning lamp in combination meter turns ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC and TCS functions. However, ABS and EBD functions operate normally.

ABS FUNCTION

ABS warning lamp and SLIP indicator lamp in combination meter turn ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC, TCS and ABS functions. However, EBD functions operate normally.

EBD FUNCTION

ABS warning lamp, brake warning lamp and SLIP indicator lamp in combination meter turn ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC, TCS, ABS and EBD functions.

Display Item List

Refer to " DTC INDEX ".

DATA MONITOR

WORK SUPPORT

VDC warning lamp in combination meter turns ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC and TCS functions. However, ABS and EBD functions operate normally.

ABS warning lamp and SLIP indicator lamp in combination meter turn ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC, TCS and ABS functions. However, EBD functions operate normally.

ABS warning lamp, brake warning lamp and SLIP indicator lamp in combination meter turn ON when a malfunction occurs in system [ABS actuator and electric unit (control unit)]. The control is suspended for VDC, TCS, ABS and EBD functions.

DETAILED FLOW

1. COLLECT INFORMATION FROM THE CUSTOMER Get detailed information from the customer about the symptom (the condition and the environment when the incident/malfunction occurred) using the diagnostic worksheet. Refer to " «DIAGNOSTIC WORK SHEET»(ref-675599-S27274574062014120500000) ". : GO TO 2.
2. PERFORM SELF DIAGNOSTIC RESULT Perform self diagnostic result. Refer to " «CONSULT FUNCTION (ABS)»(ref-675599-S00147093492014120500000) ". Are any DTCs displayed? YES: Refer to " «DTC INDEX»(ref-675599-S09934599962014120500000) ". NO: GO TO 3.
3. CHECK SYMPTOM OPERATING CONDITION Check that the symptom is a normal operating condition. Refer to " «DESCRIPTION»(ref-675599-S31424384972014120500000) ". Is the symptom a normal operating condition? YES: Inspection End. NO: GO TO 4.
4. CHECK WARNING AND INDICATOR LAMPS OPERATION Check ABS and brake warning lamps, and VDC OFF and SLIP indicator lamps operation. Refer to " «METER SYSTEM: SYSTEM DESCRIPTION»(ref-675593-S40444546932014120500000) ". Is ON/OFF timing normal? YES: GO TO 5. NO: Perform warning lamp diagnosis. Refer to " «COMPONENT FUNCTION CHECK»(ref-675599-S05236915712014120500000) " (ABS warning lamp), " «COMPONENT FUNCTION CHECK»(ref-675599-S40615230792014120500000) " (brake warning lamp), " «COMPONENT FUNCTION CHECK»(ref-675599-S33732313722014120500000) " (VDC OFF indicator lamp) or " «COMPONENT FUNCTION CHECK»(ref-675599-S32947731682014120500000) " (SLIP indicator lamp).
5. PERFORM DIAGNOSIS APPLICABLE TO THE SYMPTOM Perform diagnosis applicable to the symptom. Refer to " «SYMPTOM TABLE»(ref-675599-S38296975262014120500000) ". : GO TO 6.
6. FINAL CHECK Perform self diagnostic result again, and check that the malfunction is repaired. After checking, erase the self diagnosis memory. Refer to " «CONSULT FUNCTION (ABS)»(ref-675599-S00147093492014120500000) ". : Inspection End.

Scheme 44

Work Procedure

1. PERFORM THE NEUTRAL POSITION ADJUSTMENT FOR THE STEERING ANGLE SENSOR Perform the neutral position adjustment for the steering angle sensor. : Refer to " «WORK PROCEDURE»(ref-675599-S14805241842014120500000) ".

Component Function Check

1. CHECK PARKING BRAKE SWITCH OPERATION Check that brake warning lamp in combination meter turns ON/OFF when parking brake is actuated. Is the inspection result normal? YES: Inspection End. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S33220119552014120500000) ".

1. CHECK VDC OFF SWITCH OPERATION Check that VDC OFF indicator lamp in combination meter turns ON/OFF when VDC OFF switch is operated. Is the inspection result normal? YES: Inspection End. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S29096455332014120500000) ".

1. CHECK ABS WARNING LAMP FUNCTION Check that ABS warning lamp in combination meter turns ON for approximately 2 seconds after ignition switch is turned ON. Is the inspection result normal? YES: Inspection End. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S20481321442014120500000) ".

1. CHECK BRAKE WARNING LAMP FUNCTION (1) Check that brake warning lamp in combination meter turns ON for approximately 2 seconds after ignition switch is turned ON. Is the inspection result normal? YES: GO TO 2. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S20587941872014120500000) ".
2. CHECK BRAKE WARNING LAMP FUNCTION (2) Check that brake warning lamp in combination meter turns ON/OFF when parking brake is operated. Is the inspection result normal? YES: GO TO 3. NO: Check parking brake switch system. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S33220119552014120500000) ".

1. CHECK VDC OFF INDICATOR LAMP FUNCTION Check that VDC OFF indicator lamp in combination meter turns ON for approximately 2 seconds after ignition switch is turned ON. Is the inspection result normal? YES: Inspection End. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S23559933432014120500000) ".

1. CHECK SLIP INDICATOR LAMP FUNCTION Check that slip indicator lamp in combination meter turns ON for approximately 2 seconds after ignition switch is turned ON. Is the inspection result normal? YES: Inspection End. NO: Proceed to diagnosis procedure. Refer to " «DIAGNOSIS PROCEDURE»(ref-675599-S33637215812014120500000) ".