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ANTI-LOCK BRAKING SYSTEM
Fault finding - Introduction
MK70 ABS
Vdiag No: 04
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3. REMINDERS
Procedure
To run diagnostics on the vehicle computers, switch on the ignition using the key.
Faults
Faults are declared as either present or stored (depending on whether they appeared in a certain context and have
disappeared since, or whether they remain present but have not been diagnosed within the current context).
The present or stored status of faults should be taken into consideration when the diagnostic tool is switched on
after the + after ignition feed (without any system components being active).
For a present fault, apply the procedure described in the Interpretation of faults section.
For a stored fault, note the faults displayed and apply the instructions in the Notes section.
If the fault is confirmed when the instructions in the Notes section are applied, the fault is present. Deal with the
fault.
If the fault is not confirmed, check:
–the electrical lines which correspond to the fault,
–the connectors on these lines (corrosion, bent pins, etc.),
–the resistance of the component detected as faulty,
–the condition of the wires (melted or split insulation, wear).
Conformity check
The aim of the conformity check is to check statuses and parameters that do not produce a fault display on the
diagnostic tool when they are inconsistent. Therefore, this stage is used to:
–carry out fault finding on faults that do not have a fault display, and which may correspond to a customer
complaint.
–check that the system is operating correctly and that there is no risk of a fault recurring after repairs.
This section gives the fault finding procedures for statuses and parameters and the conditions for checking them.
If a status is not behaving normally or a parameter is outside the permitted tolerance values, consult the
corresponding fault finding page.
Customer complaints - Fault finding chart
If the test with the diagnostic tool is OK but the customer complaint is still present, the fault should be processed by
customer complaint.
A summary of the overall procedure to follow is provided on the following page in the
form of a flow chart.
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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
