2009 RENAULT TWINGO steering

38C-8
MR-413-X44-38C000$141_eng.mif
V1
38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Operating diagram
Number Description
1Computer
2Hydraulic unit (8 solenoid valves)
3Electric power assisted steering
4Instrument panel - engine management
5Passive brake servo
6Brake lights switch
7Diagnostic socket
8Battery
9Wheel speed sensor
10Target
11Brake discs
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$141_eng.mif

38C-9
MR-413-X44-38C000$188_eng.mif
V1
38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Function
EBD (electronic braking distribution):
The EBD optimises the brakeforce distribution between the front and rear axles. This function ensures vehicle
stability under braking.
ABS (anti-lock braking system):
The ABS prevents the wheels from locking when braking. This function allows the vehicle to be steered under
braking and ensures vehicle stability under braking.
MSR (engine torque control):
This is a function that enhances the ABS function. It prevents the drive wheels from spinning excessively when lifting
off the accelerator or changing down a gear on a low grip surface, by allowing the engine to regulate the driving
torque of the engine (resisting torque compensation) to "relaunch" the wheels.
The system also supplies the other computers with information on the vehicle speed via a wire connection for the
radio, the power steering and the electric sunroof, and via the multiplex network for the other computers. The ABS
computer supplies the multiplex network with the odometry for the instrument panel and navigation system. If heavy
braking produces very rapid deceleration, the ABS computer sends out a request to the UCH (passenger
compartment connection unit) via the multiplex network to ask it to switch on the hazard warning lights (depending
on the law in the relevant country).
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$188_eng.mif

38C-10
MR-413-X44-38C000$235_eng.mif
V1
38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Role of components
Wheel speed sensor:
Gives the speed of each of the vehicle's wheels. The analysis of the right/left-hand speeds makes it possible to
calculate in what direction the vehicle is turning.
Brake lights switch:
Visual indication of the brake pedal position. It makes it possible to tell if the driver is braking or not.
Wire connection (vehicle speed):
The ABS computer is best suited to transmit the vehicle speed to the other computers. To do this, the ABS transmits
the vehicle speed on the CAN network. However, some computers are not connected to the CAN network, this is
why the ABS is fitted with a "vehicle speed" wire output. Fault finding is not run on this connection by the ABS
computer. This enables the consumers of this signal to perform the necessary checks during their own fault finding
procedure, or to check the connection by observing the customer complaint on the consumer (for example, increase
in the volume of the radio if the speed increases, electric power-assisted steering).
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$235_eng.mif

38C-13
MR-413-X44-38C000$376_eng.mif
V1
38C
ANTI-LOCK BRAKING SYSTEM
Diagnostics - Configuration and Programming
SETTINGS
VP001: Enter VIN.
This command allows the vehicle identification number to be entered into the computer.
Use this command each time the computer is replaced. The VIN (VF...) is engraved on the manufacturer's
plate on the front right-hand door pillar and stamped on the body under the windscreen on the left-hand
side.
VP004: Vehicle parameters.
This command configures the engine type configuration, the braking definition and the body type.
Select command VP004 on the diagnostic tool.
VP006: Write last After Sales operation date.
Whenever the ABS system is worked on in the shop, the date must be entered.
Select command VP006 "Write date of last After-Sales operation" on the diagnostic tool.
Enter the operation date with the tool keyboard.
VP007: Tachometric index.
This command is used to program the computer memory with the index required to calculate vehicle speed
from the speed at which the wheels turn.
The MK70 ABS computer supplies the vehicle speed signal to all areas where this information is needed
(instrument panel, engine management, etc.). This vehicle speed signal replaces the one supplied by the
speed sensor located on the gearbox.
The ABS computer calculates the vehicle speed from the speed of the wheels and the circumference of the
tyres fitted on the vehicle.
The tyre circumference must be programmed into the memory of a new computer. This consists of entering
an index "X" using command VP007 "Tachometric index" on the diagnostic tool.
Once the number has been entered using the VP007 command, delete the fault in the computer memory and then
switch off the ignition. Use parameter PR030 Tachometric index to check that the index entered has been correctly
registered.
CONFIGURATIONS
CF079: Gearbox type.
Use this command to configure the gearbox type fitted on the vehicle.
OTHER COMMANDS
LC008: Gearbox type.
This command tells you the gearbox type configured on the vehicle. Note:
The vehicle speed is delivered by wire (connection 47F) to the radio, to the electric power-assisted steering, to
the electric sunroof and by the multiplex network for the other computers.
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$376_eng.mif