62C-19
MR-413-X44-62C000$455_eng.mif
V1
MANUAL AIR CONDITIONING
Fault finding - Function62C
Vehicle
multiplex
network
Summary diagram of components controlled or managed by the UCH:
Summary diagram of components controlled or managed by the injection computer Rear screen de-icing and
rear-view mirror de-icer
(depending on version)External temperature
sensor
(depending on
version)
Actuator control Sensor management
UCH
Air conditioning request
managementHeated rear screen control
management
Relay No. 1 for
the Passenger
Compartment
Heating
ResistorsRelay No. 2 for
the Passenger
Compartment
Heating
ResistorsAir conditioning
compressorEngine cooling
fan assemblyEngine
coolant
temperature
sensorRefrigerant
fluid
pressure
sensor
Actuator control Sensor management
Engine injection computer
Management of the cold loop (refrigerant pressure, engine cooling fan activation request,
compressor activation authorisation, etc.)
Key:
Wire connections =
Multiplex connections =
62C-58
MR-413-X44-62C000$910_eng.mif
V1
MANUAL AIR CONDITIONING
Fault finding - Fault finding charts62C
ALP 10 Inefficient rear screen de-icing/demisting
NOTESCarry out this conformity check after a full check using the diagnostic tool (fault
reading, especially UCH and injection faults and configuration checks).
Check that the fuses are sound.
Use a multimeter and a 21 W test light.
Use the Wiring Diagram Technical Note, New Twingo.
Special notes:
Check that the inside of the windows are not greasy as this reduces the efficiency of
the de-icing.
Note:
The de-icing control is only authorised when the engine is running to save
power. The rear screen de-icer is controlled by pressing the rear screen de-icer
button (with time delay and rear-view mirror de-icer if fitted).
Ensure that there are no water leaks in the passenger compartment which would significantly increase the
moisture and reduce the effectiveness of the demisting function (see ALP 12 if the fault is noted).
Is the fault still present?
YES NO
Check that the UCH receives the signal about the
status and operation of the engine. In the Cold Loop
screen, status ET142 Engine operating phase
should display RUNNING.
Is status ET142 RUNNING?
YES
End of fault finding procedure.
NOCarry out fault finding on the UCH
(interpretation of status ET142) and on the
multiplex network.
AFTER REPAIRCarry out a complete check with the diagnostic tool.