62C-16
MR-413-X44-62C000$455_eng.mif
V1
MANUAL AIR CONDITIONING
Fault finding - Function62C
General operation
The air conditioning system is composed of four sub-functions: heating, cold loop, passenger compartment
ventilation and user selection. Fault finding on the air conditioning is performed in two different ways using the
diagnostic tool.
The first procedure consists of performing fault finding on each computer which allows dialogue to be established
with just one computer (select the UCH computer).
The second procedure consists of performing fault finding on each function which allows communication with both
computers of the air conditioning function.
Description of the sub-functions:
Heater sub-system: this sub-system includes everything relating to the production of warm air in the vehicle and
management of the heated rear screen.
The UCH computer controls the rear screen de-icing.
The injection computer manages passenger compartment heating resistor actuation
Cold loop sub-system: this sub-system includes everything involved in the production of cold air in the vehicle.
The computers concerned include:
The injection computer, which authorises compressor activation and controls the compressor and motor-driven fan
assemblies.
The UCH, which authorises or denies the request for compressor activation from the air conditioning control panel to
the injection computer in accordance with the condition of the passenger compartment blower and the exterior
temperature (depending on the equipment).
User selection sub-function: This sub-function includes everything used to transmit the user's requests (pressing
buttons). The computer involved is the UCH computer.
