GF42.45-D-5118H ESP Control Unit, Component Description
GF42.45-D-5118H ESP Control Unit, Component Description
72 Traction systems hydraulic unit
N30/4 ESP control unit
Location
The ESP control unit is located at the traction system hydraulic unit in the left of the engine compartment.
Task
The ESP control unit reads in the signals of the following components:
^ Stop lamp switch (S9/1), this is required for the detection and evaluation of the switch position of the dual contact switch (normally open contact and normally closed contact) when the brake is operated.
^ Left front rpm sensor (L6/1), right front rpm sensor (L6/2), left rear rpm sensor (L6/3) and right rear rpm sensor (L6/4), these supply the current wheel speed signals from the respective wheels.
^ Brake pressure sensor, this is located in the traction system hydraulic unit, detects the actuation of the brake by the driver and records the brake pressure.
^ ASR OFF button (N72/1s5), this records the driver's requirement "switch off acceleration slip regulation (ASR)" when the ASR OFF button is pressed.
^ Yaw rate, lateral and longitudinal acceleration Location sensor (B24/15), this records the rotational speed about the vertical axis and the lateral and longitudinal acceleration of the vehicle.
^ Steering angle sensor (N80b1), this detects the steering angle.
^ Backup lamp switch (S16/2) on vehicles with transmission 711.6, in order to detect that reverse gear is engaged.
^ Transmission neutral position switch (S164) on vehicles with transmission 711.6 and except code (MJ6) Engine start/stop system, to detect when the transmission is in the neutral position or when a gear is engaged.
Amongst others information is received from the following control units via the Controller Area Network-Bus Class C (engine compartment) (CAN C):
ETC [EGS] control unit (N15/5), with transmission 722.6
^ Selector lever position
ETC [EGS] control unit (N15/3), with transmission 722.6
^ Wheel torque factor, overall gear ratio
^ Actual gear engaged/target gear, i.e. engaged gear, gear to be shifted, can be shown via STAR DIAGNOSIS
CDI control unit (N3/20), with OM 642
^ Engine torque
^ Accelerator pedal position
^ Requirement torque, Electronic Stability Program (Electronic-Stability-Program) (ESP)
^ Terminal 61 ON
^ Neutral position or engaged gear via transmission neutral position switch, with transmission 711.6 and with code (MJ6) Engine start/stop system
CDI control unit (N3/21), with OM 646
^ Engine torque
^ Accelerator pedal position
^ ESP requirement torque
^ Terminal 61 ON
^ Neutral position or engaged gear via transmission neutral position switch, with transmission 711.6 and with code (MJ6) Engine start/stop system
ME-SFI [ME] control unit (N3/23), with M 272
^ Engine torque
^ Accelerator pedal position
^ ESP requirement torque
^ Terminal 61 ON
The ESP control unit processes these signals and evaluates them. In the case of the evaluated data a distinction is made between the data for describing the associated physical quantity, the calculation of further physical quantities which are required for the computations of control functions and information for describing the switch status of a switch or sensor.
The ESP control unit calculates the following values:
^ Acceleration
^ Deceleration
^ Wheel slip
^ Drive slip
^ Decel slip
The values mentioned are required to implement the control functions of the following control systems:
^ ESP
^ Antilock brake system (ABS)
^ Brake Assist (BAS)
^ Electronic traction system (ETS), with code (ZG1) Engageable all-wheel drive or code (ZG2) Permanent all-wheel drive or code (ZG3) Gear reduction for all-wheel drive or code (ZG4) Permanent all-wheel drive with gear reduction
^ Acceleration Slip Regulation (ASR)
^ Electronic brake force distribution (EBV)
^ Start-off assist (AAS), with code (E07) Starting-off aid
^ Engine braking regulation (EBR)
Depending on the control functions the following components are actuated by the ESP control unit:
^ Traction system hydraulic unit
^ ESP indicator lamp (A1e14), traction warning indicator lamp (A1e15), ABS indicator lamp (A1e16) and BAS indicator lamp (A1e36) (except code (JK3) High-end instrument cluster with speedometer in km), which are integrated in the instrument cluster (A1)
Amongst others the ESP control unit transmits other information to the following control units:
EGS control unit, with transmission 722.6
^ Vehicle lateral acceleration at the center of gravity
^ Cruise control active, with code (MS1) Cruise control
^ ESP request shift into "N" (neutral), power flow interruption, transmission/rear axle
^ Signal from stop lamp switch
^ Adjusted braking torque, change of shift strategy, brake the vehicle
^ Wheel speeds and direction of rotation
CDI control unit (N3/20), with OM 642
^ Stop lamp switch
^ Wheel speeds and direction of rotation
^ Cruise control mode, with code (MS1) cruise control
^ Set braking torque
^ Torque request
CDI control unit (N3/21), with OM 646
^ Stop lamp switch
^ Wheel speeds and direction of rotation
^ Cruise control mode, with code (MS1) cruise control
^ Set braking torque
^ Torque request
ME-SFI [ME] control unit (N3/23), with M 272
^ Stop lamp switch
^ Wheel speeds and direction of rotation
^ Cruise control mode, with code (MS1) cruise control
^ Set braking torque
^ Torque request