87B-2
MR-413-X44-87B000$048.mif
V5
87B
PASSENGER 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 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
3. REMINDER
To run fault finding on the vehicle computers, switch on the ignition.
To cut off the + after ignition feed, proceed as follows:Vehicle(s): New Twingo
Function concerned: Passenger compartment
connection unitName of computer: UCH
Vdiag No.: 44
Special tooling required
Multimeter
Elé. 1681 Universal bornier
–Switch on the ignition with the key.
–Connect the diagnostic tool and perform the required operations.
–Switch off the ignition with the key.
–Disconnect the diagnostic tool.
–Switch off the ignition.
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UCH
Vdiag No.: 44
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UCH
Vdiag No.: 44PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Introduction87B
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.
Tactile 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 to another wire.
If a fault is detected, repair or replace the wiring harness.
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ENGINE HARNESS
FRONT ENGINE WIRING & ADDITIONAL HEADLIGHTS
DOOR WIRING
CEILING WIRING
PASSENGER COMPARTMENT WIRING
REAR BUMPER WIRING
TAILGATE WIRING
1UCH
2Passenger Compartment Relay/Fuse Box
3Electric power-assisted steering.
4Transponder ring.
5Air conditioning panel.
6One touch window/anti-pinch module.
7Exterior temperature sensor.
8Rain/light sensor & interior temperature sensor.
9Anti-pinch/sunroof.
2ABS computer.
2Injection computer.
3Preheating unit.
4Sequential gearbox computer.
5Engine fuse and relay box.
6Alternator.
7
2
61
2
3
5
4
8
5
7
43
1
6
9
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding
- List and location of components
MR-413-X44-87B000$096.mif
UCH
Vdiag No.: 44
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87B
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults
DF001
PRESENT
OR
STOREDUCH
1.DEF : Internal electronic fault
NOTESConditions for applying the fault finding procedure to stored faults:
The fault is declared present after the ignition is switched off and back on.
If the fault is stored, clear the fault, switch off the ignition and disconnect the F8 (15A) fuse of the UCH supply
(component code 645) on the passenger compartment fuse and relay box (component code 1016).
–Refit the fuse and switch the ignition back on.
–Request locking and then unlocking, then start the engine.
Check the condition and connection of the PE1, PE2 and PE3 connectors of the UCH (component code 645)
(tabs pushed back, oxidised, broken).
If the connector(s) are faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring
repair, Wiring: Precautions for repair), repair the wiring, otherwise replace the wiring.
Check for + after ignition feed on connection AP43 of component 645.
Check for + accessories feed on connection SP2 (for vehicles fitted with a manual gearbox) or SP15
(for vehicles fitted with a sequential gearbox) of component 645.
Check for earth on connection NAM of component 645. Check the earth on connection MAM of component 645.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the fault reappears as stored, contact Techline.
If the fault does not reappear, switch the lighting, wipers, vehicle locking and climate control request controls on
and off several times, then read the faults again.
If the fault is still present. Do not operate on the computer, contact Techline.
AFTER REPAIRIf the computer has been replaced (at the request of the Techline): reconfigure the new
UCH (see Configurations and programming).
Deal with any other faults.
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Vdiag No.: 44
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults
UCH
Vdiag No.: 44
87B
DF011
PRESENT
OR
STOREDRAIN/LIGHT SENSOR CIRCUIT
1.DEF : Open circuit or short circuit
NOTESConditions for applying the fault finding procedure to stored faults:
Switch on the ignition, activate automatic headlighting by quickly performing the
following manipulation twice: control stalk (component code 209) on zero position →
control stalk (component code 209) in Side light position.
Status ET114 “Wiper request by rain sensor” should be “Low speed” or “High
speed” when the water runs over the rain/light sensor on the windscreen or
status ET115 “Request for lights to be switched on by light sensor” should be
“Present” by placing an opaque cover over the rain/light sensor.
Note:
If there is an open circuit on connection BPT, there is a malfunction on the
electric windows, rain/light sensor, interior light(s) and luggage compartment
light.
Check that the vehicle has a rain/light sensor (component code 1415).
Check that the function is not deactivated, quickly perform the following cycle twice to activate the automatic
headlighting function: Monolever (component code 209) OFF → Monolever (component code 209) in Side light
ON position.
Check that the vehicle has a rain/light sensor (component code 1415).
Check that LC044 "Rain/light sensor" displays "Present". If not, carry out CF035 "Rain/light sensor".
Check that LC096 "Automatic wiper function" displays "With". If not, carry out CF194 "Automatic wiper
function".
Check that LC095 "Automatic headlight function", displays "With". If not, carry out CF193 "Automatic
headlight function".
Check the condition and the positioning of fuses F2 (15A), F8 (15A), F19 (5A), F27 (5 A) depending on the
equipment and F29 (15A) on the passenger compartment fuse and relay box (component code 1016).
Replace the fuse(s) or repair if necessary.
Check the condition and connection of the PE1, PE2 and PE3 connectors of the UCH (component code 645)
(tabs pushed back, oxidised, broken).
Check for + after ignition feed on connection AP43 of component 645.
Check for + accessories feed on connection SP2 (for vehicles fitted with a manual gearbox) or SP15
(for vehicles fitted with a sequential gearbox) of component 645.
Check for earth on connection NAM of component 645. Check the earth on connection MAM of component 645.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
AFTER REPAIRCarry out another fault finding check on the system.
Clear the stored faults.
Deal with any other faults.
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults
UCH
Vdiag No.: 44
87B
Rain/light sensor check:DF011
CONTINUED
Check the continuity and insulation of the following connections:
●Connection code AP43,
●Connection code SP2,
●Connection code SP15.
Between components 645 and 1016.
●Connection code MAN or MAM between component 645 and earth MAN or MAM (depending on the driving
layout, right- or left-hand drive).
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the connections are correct, check the rain/light sensor (component code 1415).
Check the condition and connection of the 3-track rain/light sensor connector (component code 1415) (tabs
bent, broken or oxidised).
Check for + 12 V on connection BPT of component 1415.
Check for earth on connection MAM of component 1415.
Check the continuity and insulation of the following connections:
●Connection code BPT between components 645 and 1415.
●Connection code 14S between components 645 and 1415.
●Connection code MAM between components 1415 and earth.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check that the sensor is not dirty.
Check that the sensor is correctly bonded to the windscreen. (see MR 411 85A, Wipers - Washers, Rain and
light detector: Removal - Refitting)
If the fault is still present, replace the rain/light sensor (component code 1415).
If the fault is still present, contact the Techline.
AFTER REPAIRCarry out another fault finding check on the system.
Clear the stored faults.
Deal with any other faults.
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MR-413-X44-87B000$384.mif
V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults
UCH
Vdiag No.: 44
87B
DF012
PRESENT
RIGHT-HAND DIRECTION INDICATOR CIRCUIT
CC.0 : Short circuit to earth
C0.1 : Open circuit or short circuit to + 12 V
1.DEF : Bulb(s) not working or short circuit to + 12 V
NOTESConditions for applying the fault finding procedure to stored faults:
The fault appears after:
The right-hand indicator stalk is activated.
OR
Activation of AC023 Right-hand indicator.
Check that fuses F13 (30A) and F15 (5 A) are sound and correctly fitted in the passenger compartment fuse and
relay box (component code 1016).
Check the bulbs and condition of the bulb supports.
Replace the bulbs if necessary.
With command AC023 Right-hand indicator running, check for + 12 V on the following connection:
●Connection code 64D.
Between components 256 and 645.
Between components 268 and 645.
Between components 173 and 645.
Check the continuity on the following connection:
●Connection code 64D.
Between components 256 and 645.
Between components 268 and 645.
Between components 173 and 645.
Check for earth on the following connections:
●Connection code MAS between component 256 and earth MAS.
●Connection code MAS between component 268 and earth MAS.
●Connection code MF between component 173 and earth MF.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the feeds and earths are correct, check the monolever (component code 209).
If the feeds and earths are not correct, check the condition and connection of the horn and lights switch
connector (component code 209) and the UCH 40-track connector PE2 (component code 645) (tabs bent,
broken or oxidised).
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
AFTER REPAIRCarry out another fault finding check on the system.
Clear the stored faults.
Deal with any other faults.
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PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of faults
UCH
Vdiag No.: 44
87B
DF012
CONTINUED
Checking the monolever (component code 209):
With command AC023 Right-hand indicator running, check for + 12 V on the following connection:
●Connection code 64S between components 209 and 645.
If the connection is faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring repair,
Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If there is no + 12 V, check the insulation, continuity and the absence of interference resistance on the
following connections:
●Connection code 64S between components 209 and 645.
●Connection code BPA2 between components 1016 and 209.
●Connection code BPA3 between components 1016 and 209.
●Connection code MAN or MAM between component 209 and earth MAN or MAM (depending on the driving
layout, right- or left-hand drive).
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the feeds, earths and connections of the monolever (component code 209) are correct, replace the monolever
(component code 209). (see MR 411 Mechanical systems 84A, Controls - Signals, Lighting and signals
switch: Removal - Refitting)
If the fault is still present, contact the Techline.
AFTER REPAIRCarry out another fault finding check on the system.
Clear the stored faults.
Deal with any other faults.