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Chassis
"The repair procedures given by the manufacturer in this document are based on the
technical specifications current when it was prepared.
The procedures may be modified as a result of changes introduced by the
manufacturer in the production of the various component units and accessories from
which his vehicles are constructed."
V1
All rights reserved by Renault s.a.s.
Edition Anglaise
Copying or translating, in part or in full, of this document or use of the service part
reference numbering system is forbidden without the prior written authority of
Renault s.a.s.
© Renault s.a.s.
V1 MR-413-X44-38C000$000_engTOC.mif
ANTI-LOCK BRAKING SYSTEM
MK70 ABS
Vdiag No: 04
Fault finding - Introduction 38C - 2
Fault finding - List and location of components 38C - 7
Fault finding - Operating diagram 38C - 8
Fault finding - Function 38C - 9
Fault finding - Role of components 38C - 10
Fault finding - Defect and safe modes 38C - 11
Diagnostics - Replacing parts 38C - 12
Diagnostics - Configuration and Programming 38C - 13
Fault finding - Fault summary table 38C - 14
Fault finding - Interpretation of faults 38C - 15
Fault finding - Conformity check 38C - 51
Diagnostic - Summary table of statuses and parameters 38C - 52
Fault finding - Interpretation of statuses 38C - 53
Fault finding - Dealing with command modes 38C - 57
Fault finding - Command summary table 38C - 58
Fault finding - Dealing with command modes 38C - 59
Fault finding - Customer complaints 38C - 64
Fault finding - Fault Finding Chart 38C - 65
38C
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ANTI-LOCK BRAKING SYSTEM
Fault finding - Introduction
1. SCOPE OF THIS DOCUMENT
This document presents the fault finding procedure applicable to all computers with the following specifications:
2. PREREQUISITES FOR FAULT FINDING
Documentation type
Fault finding procedures (this manual):
–Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
–Visu-Schéma (CD-ROM), paper.
Type of diagnostic tools
–CLIP
Special tooling required
Vehicle: New Twingo
Function concerned: MK70 ABSComputer name: TEVES ABS
Vdiag No.: 04
Special tooling required
Multimeter
Elé. 1681 Universal bornier
ABS_V04_PRELI
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$047_eng.mif
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Fault finding - Introduction
MK70 ABS
Vdiag No: 04
38C
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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Vdiag No: 04ANTI-LOCK BRAKING SYSTEM
Fault finding - Introduction38C
4. FAULT FINDING PROCEDURE
Check the battery charge and the
condition of the fuses
Print the system fault finding log
(available on CLIP)
Connect CLIP
no
Dialogue with
computer?
yes
Read the faults
no
Faults
present
yes
Deal with present faults
Deal with stored faults
no
The cause is
still presentFault
solved
yes
Refer to ALP No. 1
Conformity check
no
The cause is
still presentFault
solved
Use fault finding charts
(ALPs)
no
The cause is
still presentFault
solved
Contact the Techline with the
completed fault finding log
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Fault finding - Introduction
MK70 ABS
Vdiag No: 04
38C
4. FAULT FINDING PROCEDURE (CONTINUED)
Wiring check
Fault finding problems
Disconnecting the connectors and/or manipulating the wiring harness may temporarily remove the cause of a
fault.
Electrical measurements of voltage, resistance and insulation are generally correct, especially if the fault is not
present when the analysis is made (stored fault).
Visual inspection of the connection:
●Check that the connector is connected correctly and that the male and female parts of the connection are
correctly coupled.
Visual inspection of the area around the connection:
●Check the condition of the mounting (pin, strap, adhesive tape, etc.) if the connectors are attached to the
vehicle.
●Check that there is no damage to the wiring trim (sheath, foam, adhesive tape, etc.) near the wiring.
●Check that there is no damage to the electrical wires at the connector outputs, in particular on the
insulating material (wear, cuts, burns, etc.).
Disconnect the connector to continue the checks.
Visual inspection of the plastic casing:
●Check that there is no mechanical damage (casing crushed, cracked, broken, etc.), in particular to the
fragile components (lever, lock, openings, etc.).
●Check that there is no heat damage (casing melted, darker, deformed, etc.).
●Check that there are no stains (grease, mud, liquid, etc.).
Visual inspection of the metal contacts:
(The female contact is called CLIP. The male contact is called TAB.)
●Check that there are no bent contacts (the contact is not inserted correctly and can come out of the back
of the connector). The spring contact of the connector when pulling the wire slightly.
●Check that there is no damage (folded tabs, clips open too wide, blackened or melted contact, etc.).
●Check that there is no oxidation on the metal contacts. Note:
Carry out each requested check visually. Do not remove a connector if it is not required.
Note:
Repeated connections and disconnections alter the functionality of the connectors and increase the risk of poor
electrical contact. Limit the number of connections/disconnections as much as possible.
Note:
The check is carried out on the 2 parts of the connection. There may be two types of connections:
–Connector / Connector
–Connector / Device
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Fault finding - Introduction
MK70 ABS
Vdiag No: 04
38C
Visual inspection of the sealing:
(Only for watertight connectors)
●Check for the seal on the connection (between the 2 parts of the connection).
●Check the seal at the back of the connectors:
–For unit joints (1 for each wire), check that the unit joints are present on each electrical wire and that
they are correctly positioned in the opening (level with the housing). Check that plugs are present on
openings which are not used.
–For a grommet seal (one seal which covers the entire internal surface of the connector), check that
the seal is present.
–For gel seals, check for gel in all of the openings without removing the excess or any protruding
sections (it does not matter if there is gel on the contacts).
–For hotmelt sealing (heat-shrink sheath with glue), check that the sheath has contracted correctly on
the rear of the connectors and electrical wires, and that the hardened glue comes out of the side of
the wire.
●Check that there is no damage to any of the seals (cuts, burns, significant deformation, etc.).
If a fault is detected, repair or replace the wiring (see Technical Note 6015A, Repairing electrical wiring, Wiring:
Precautions for repair)
5. FAULT FINDING LOG
You will always be asked for this log:
–when requesting technical assistance from Techline,
–for approval requests when replacing parts for which approval is mandatory,
–to be attached to monitored parts for which reimbursement is requested. The log is needed for
–warranty reimbursement, and enables better analysis of the parts removed.
6. SAFETY INSTRUCTIONS
Safety rules must be observed during any work on a component to prevent any damage or injury:
–check the battery voltage to avoid incorrect operation of computer functions,
–use the proper tools.
It is forbidden to carry out a road test with the diagnostic tool in dialogue with the ECU because the ABS and
Electronic Brake Distribution functions are deactivated. Braking pressure is identical on both vehicle axles
(risk of a spin under heavy braking).IMPORTANTIMPORTANT
Any fault on a complex system requires thorough fault finding with the appropriate tools. The
FAULT FINDING LOG, which should be completed during the procedure, enables you to keep
track of the procedure which is carried out. It is an essential document when consulting the
manufacturer.
IT IS THEREFORE MANDATORY TO FILL OUT A FAULT FINDING LOG EACH TIME FAULT FINDING IS
CARRIED OUT.
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ANTI-LOCK BRAKING SYSTEM
Fault finding - List and location of components
The computer/hydraulic unit assembly:
●Located to the left of the bulkhead in the engine compartment.
Front wheel sensors:
●Screwed into the stub-axle, each front sensor has an intermediate connector located behind the plastic wheel
arch liner.
Rear wheel sensor intermediate connectors:
●Located in a sealed unit under the vehicle.
Rear wheel sensors:
●Screwed into the rear brake drum flange.
Brake light switch:
●Located on the pedal assembly.
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$094_eng.mif
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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