S42.47-0008-79
Block diagram (with engine 200 or engine 699) |
A1/1 | Instrument cluster (KI) control unit | N30/4 | Electronic Stability Program (ESP) control unit | |
A1/1e17 | Anti-lock braking system indicator lamp | N30/4b1 | Master brake cylinder brake pressure sensor | |
A1/1e32 | ESP®/ASR OFF warning lamp | N45 | Transfer case control unit (VG) (with code ZG3 (Engageable all-wheel drive with gear reduction) or with code ZG4 (Permanent all-wheel drive with gear reduction)) | |
A1/1e41 | Electronic Stability Program warning lamp | N50 | Fuse and relay module control unit (SRM) | |
A1/1e51 | Brake system warning lamp | N74s6 | Downhill Speed Regulation (DSR) button (with code E2D (Downhill Speed Regulation)) | |
A1/1p13 | Multifunction display | N80 | Steering column tube module (MRM) control unit | |
A40 | Audio/COMAND control panel | N87/6 | Radio (Audio/COMAND) | |
A40/2 | Right lower control panel (LCPR [UBFR]) control unit | N93 | Central gateway (CGW) | |
A40/2s4 | ESP® OFF button | S9/3 | Stop lamp switch | |
B37/4 | Accelerator pedal module | S16/2 | Backup lamp switch (with manual transmission) | |
E3 | Rear left lamp unit (without code LG7 (LED High Performance headlamp)) | S75/1 | Indicator switch 1st gear (with manual transmission) | |
E3/1 | Rear left LED lamp unit (with code LG7 (LED High Performance headlamp)) | S76/3 | Rear-axle differential lock button (with code A71 (Rear-axle differential lock)) | |
H4/61 | Instrument cluster speaker | S164/3 | Transmission neutral position switch (with manual transmission) | |
K75/1 | Stop lamp relay | CAN A | Telematics CAN | |
L6/1 | Left front axle rpm sensor | CAN E | Chassis CAN | |
L6/2 | Right front axle rpm sensor | CAN HMI | User interface CAN | |
L6/3 | Left rear axle rpm sensor | CAN V | Vehicle CAN | |
L6/4 | Right rear axle rpm sensor | LIN A2 | Telephone keypad LIN | |
N3/33 | CDI control unit (with engine 699) | A | Mercedes-Benz | |
N3/34 | ME-SFI [ME] control unit (with engine 200) | B | Nissan | |
N15/3 | Electronic transmission control (EGS) control unit (with automatic transmission) | C | Default | |
N15/9 | Rear-axle differential lock control unit (with code A71 (Rear-axle differential lock)) | D | Option |
General function requirements for ADAPTIVE BRAKE
Drivetrain ready
Engine running.
ADAPTIVE BRAKE, general
ADAPTIVE BRAKE assist the driver in hazardous situations using various driver assistance systems.
To do so, the Electronic Stability Program (ESP) control unit evaluates the following signals:
Wheel speeds from rpm sensors
Steering wheel angle from the steering column tube module (MRM) control unit
Brake pressure from brake pressure sensor for master brake cylinder
Status of brake pedal from brake light switch
Status of accelerator pedal from accelerator pedal module
The system is made up of the following subfunctions:
Electronic Stability Program ESP®
Electronic brake force distribution (EBD)
Emission test, roller dynamometer mode
Anti-lock braking system (ABS)
Brake Assist System (BAS)
Downhill Driving Assist (Downhill Speed Regulation DSR)
System fault display
Electronic Stability Program ESP®
ESP® prevents the vehicle from breaking away when oversteered or understeered. Within physical limits it ensures that the vehicle does not deviate from the course specified by the driver.
Brake forces are produced selectively at the individual wheels to correct any deviations.
Furthermore, reduction of the drive torque takes place in order to increase driving stability.
The Electronic Stability Program (ESP) control unit processes the following measured quantities to determine the vehicle behavior:
Yaw rate from the integrated turn rate, lateral acceleration and longitudinal acceleration sensor
Lateral and longitudinal acceleration from the integrated turn rate, lateral acceleration and longitudinal acceleration sensor
Brake pressure from the integrated brake pressure sensor
Steering wheel angle from the steering column tube module (MRM) control unit
Engine torque:
CDI control unit (with engine 642 or engine 699)
ME-SFI [ME] control unit (with engine 200)
Engaged drive position:
Electronic transmission control (EGS) control unit (Automatic transmission with engine 200 or engine 699)
Electric controller unit for fully integrated transmission control (VGS) (N15/11) (Automatic transmission with engine 642)
Wheel speed signals from rpm sensors
If the yaw velocity measured does not match the specified value, the Electronic Stability Program (ESP) control unit generates a signal to build up or reduce brake force for the relevant wheel. The resulting forces stabilize the vehicle.
A distinction is made between the following intervention types:
Intervention in the case of oversteer
Intervention in the case of understeer
Switch ESP® to passive.
Intervention in the case of oversteer
If the vehicle begins to oversteer, brake pressure is built up at the outer front wheel. The resulting forces cause a yawing moment which counteracts rotation of the vehicle. The vehicle speed decreases as a result of the brake force at the front wheel, which also enhances stability.
Intervention in the case of understeer
If the vehicle understeers, the maximum possible lateral force at the front axle has been exceeded. In other words, the vehicle pushes via the front axle to the outer edge of the curve.
The resulting instability is counteracted by reducing the drive torque and through the following brake applications on up to 3 wheels:
Brake pressure build-up at inner rear wheel (Stage 1)
Stage 1 and additional brake pressure reductions at outer rear wheel (Stage 2)
Stage 2 and additional brake pressure build-up at inner front wheel (Stage 3)
Switch ESP® passive
The ESP® function can be switched to passive mode while the vehicle is in operation.
If the ESP® is switched to passive, the ESP®/ASR OFF warning lamp () lights up in the instrument cluster (IC) control unit.
Electronic brake force distribution (EBD)
The EBD prevents overbraking at the rear axle and increases vehicle stability when braking on bends. To do so, the EBD selectively reduces the brake pressure at the rear wheels.
Emission test, roller dynamometer mode
The ADAPTIVE BRAKE system can be set to the roller dynamometer mode to enable the vehicle to be checked. ESP®, anti-slip control (ASR), ABS and EBV are then switched into the passive mode. The anti-lock brake system indicator lamp, the ESP®/ASR OFF warning lamp and the brake system warning lamp light up in the instrument cluster control unit. A corresponding message is also shown in the multifunction display.
Anti-lock braking system (ABS)
The ABS system prevents the wheels from blocking when braking, and - as a result - it maintains the steerability and driving stability during vehicle deceleration. If a locking wheel is detected, then the brake pressure at the corresponding brake cylinder is reduced until the wheel turns again.
Brake Assist System (BAS)
The BAS detects emergency braking situations based on rapid actuation of the brake pedal and, if necessary, increases the brake pressure in order to achieve maximum deceleration. For this purpose, the Electronic Stability Program (ESP) control unit evaluates the increase in pressure in the brake system and initiates an emergency stop if a certain activation threshold is exceeded.
Additional function requirements for downhill driving assist (Downhill Speed Regulation DSR)
Downhill driving at a speed of 5 to 8 km/h
Downhill Speed Regulation (DSR) function activated by button
Downhill Driving Assist (Downhill Speed Regulation DSR)
The downhill speed regulation function maintains the setting speed by means of specific intervention by the brake system. If the function requirements are fulfilled and the accelerator pedal, brake pedal or the cruise control lever is actuated, the setting speed is then stored. This speed can be dropped below or exceeded at any time by braking or accelerating.
If the downhill speed regulation function is active, the indicator lamp of the Downhill Speed Regulation button lights up. Between 5 and 8 km/h the multifunction display shows the DSR symbol and the stored set speed.
The downhill driving assist can be switched off using the Downhill Speed Regulation (DSR) button.
System fault display
The driver is informed about the system status and about faults by the following displays in the instrument cluster (IC) control unit:
Anti-lock braking system indicator lamp
Electronic Stability Program warning lamp
Brake system warning lamp
Signals in multifunction display
If the Electronic Stability Program (ESP) control unit fails, basic braking without ABS is always available.