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8Electrical equipment
V9 MR-372-J84-87B000$TOC.mif
V9
87B
"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."
V9
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. 2008
PASSENGER COMPARTMENT CONNECTION
UNIT
UCH
Vdiag No.: 44, 48, 4C, 4D, 4F, 50
Fault finding - Introduction 87B - 2
Fault finding - System operation 87B - 7
Fault finding - Replacement of components 87B - 49
Fault finding - Configurations and programming 87B - 51
Fault finding - Fault summary table 87B - 69
Fault finding - Interpretation of faults 87B - 71
Fault finding - Conformity check 87B - 117
Fault finding - Status summary table 87B - 139
Fault finding - Interpretation of statuses 87B - 143
Fault finding - Parameter summary table 87B - 240
Fault finding - Interpretation of parameters 87B - 241
Fault finding - Command summary table 87B - 246
Fault finding - Interpretation of commands 87B - 248
Fault finding - Customer complaints 87B - 293
Fault finding - Fault Finding Chart 87B - 300
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-2
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-2V9 MR-372-J84-87B000$043.mif
187B
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50PASSENGER COMPARTMENT CONNECTION UNIT
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 document):
–Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
–Visu-Schéma (CD-ROM), paper.
Type of diagnostic tools:
–CLIP
Special tooling required:
3. REMINDERS
Procedure
To run fault finding on the vehicle computers, switch on the forced + after ignition feed.
Proceed as follows: Vehicle(s): Mégane II, Scénic II
Function concerned: UCHName of computer: UCH
Vdiag No.: 44, 48, 4C, 4D, 4F, 50.
Special tooling required
Multimeter
Elé. 1681 Universal bornier
Switch on the forced + after ignition feed:
–with the vehicle card in the card reader,
–press and hold start button (longer than 5 seconds) with start-up conditions not fulfilled,
–connect the diagnostic tool and perform the required operations.
Switching off the forced + after ignition feed:
Press the Start button twice briefly (less than 3 seconds).
ensure that the + after ignition feed has been cut off by checking that the computer indicator lights on the instrument
panel have gone out.
UCH_V44_PRELI /UCH_V48_PRELI/UCH_V4C_PRELI/
UCH_V4D_PRELI/UCH_V4F_PRELI/UCH_V50_PRELI
MR-372-J84-87B000$043.mif
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-3
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-3V9 MR-372-J84-87B000$043.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
Faults
Faults are declared present or stored (depending on whether they appeared in a certain context and have
disappeared since, or whether they remain present but are not diagnosed within the current context).
The present or stored status of faults should be taken into consideration when the diagnostic tool is used after the
forced + after ignition feed is switched on (without acting on the system components).
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 electric lines on which there is a fault;
–The connectors on those lines (corrosion, bent pins, etc.);
–The resistance of the faulty component;
–The condition of the wires (insulation melted or split, chafing, etc.).
Conformity check
The aim of the conformity check is to check data that does not produce a fault on the diagnostic tool because the
data is 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 complaints.
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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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-4
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-4V9 MR-372-J84-87B000$043.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
4. FAULT FINDING PROCEDURE
Perform a pre-diagnostic on the
system
Print the system fault finding log
(available on CLIP and in the
Workshop Repair Manual or
Technical Note)
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
yes
Use fault finding charts (ALPs)
no
The cause is still
presentFault
solved
yes
Contact the Techline with the
completed fault finding log
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-5V9 MR-372-J84-87B000$043.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
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
Look for damage under the bonnet and in the passenger compartment.
Carefully check the fuses, insulators and wiring harness routing.
Look for signs of oxidation.
Physical inspection
While manipulating the wiring harness, use the diagnostic tool to note any change in fault status from stored to
present.
Make sure that the connectors are properly locked.
Apply light pressure to the connectors.
Twist the wiring harness.
If there is a change in status, try to locate the source of the fault.
Inspection of each component
Disconnect the connectors and check the appearance of the clips and tabs, as well as the crimping (no crimping on
the insulating section).
Make sure that the clips and tabs are properly locked in the sockets.
Check that no clips or tabs have been dislodged during connection.
Check the clip contact pressure using an appropriate model of tab.
Continuity, insulation and resistance check
Check the continuity of entire lines, then section by section.
Look for a short circuit to earth, to + 12 V or with another wire.
If a fault is detected, repair or replace the wiring harness.
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-6
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
87B-6V9 MR-372-J84-87B000$043.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
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.
Procedure for disconnecting the battery:
–Switch off the ignition.
–Switch off all the electrical consumers. Wait at least 1 minute for the electronic systems to switch off.
Disconnect the battery, starting with the negative terminal.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 ESSENTIAL THAT THE FAULT FINDING LOG IS FILLED OUT EVERY TIME IT IS
REQUESTED BY TECHLINE OR THE WARRANTY RETURNS DEPARTMENT.
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-7
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-7V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
General operation:
The UCH is involved in the following five functions (shared between several computers):
1/ Access-safety function
This function is divided into three sub-functions: Access, Protection and Starting.
2/ Air-conditioning function
This function is divided into three sub-functions, which are: User selection, Heating and Cold loop (see: 62A, Air
conditioning).
In this function, the UCH manages the triggering of the passenger compartment heating resistor control relays, as
well as the heated rear screen and air conditioning indicator lights.
3/ Wiping function
This function is divided into two sub-functions, which are: Wiper control and Wiper power.
4/ Lighting function
This function is divided into two sub-functions, which are: Lighting control and Lighting power.
5/ Tyre function
This function is divided into three sub-functions which are: Tyre reception, Tyre management and Tyre display.
MR-372-J84-87B000$086.mif
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-8
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-8V9 MR-372-J84-87B000$086.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
The ACCESS/SAFETY function is divided into three sub-functions: Access, Protection and Starting.
The maximum number of Renault cards which can be programmed on the vehicle is 4. There is no master Renault
card.
1 ACCESS/SAFETY FUNCTION
1.1 SUB-FUNCTION: ACCESS
The Megane II allows:
–locking/unlocking by pressing the buttons on the Renault card (remote control function),
–locking/unlocking by pressing the central door locking button,
–locking via the Renault Anti-Intruder Device (RAID),
–automatic relocking.
If the vehicle is fitted with the hands-free function:
–hands-free unlocking of the entire vehicle, by cutting the optical beam on one of the door handles,
–hands-free boot-only unlocking by pressing the boot opening switch,
–hands-free locking (by pressing the handle closure switch or the switch located in the boot badge).
If the vehicle is fitted with:
–electric child safety locking,
–deadlocking,
–selective opening element unlocking,
–the valet card function.
1.1.1 procedure of locking/unlocking by pressing the buttons on the Renault card:
1Opening element locking motors
2Encrypted 433 MHz RF connection (315 Mhz in Japan)
3Card button pressed