62B-17
MR-413-X44-62B000$230_eng.mif
V1
62B
CLIMATE CONTROL
Fault finding - Function
GENERAL INFORMATION:
The climate control function which is fitted to the new Twingo depends on the three computers: injection, UCH and
climate control (DISTRIBUTED FUNCTION).
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 climate control computer).
The second procedure consists of performing fault finding on each function which allows communication with all
three computers belonging to the CLIMATE CONTROL function.
DESCRIPTION OF THE OPERATION OF THE CLIMATE CONTROL COMPUTER:
The climate control computer controls the passenger compartment ventilation, the distribution motor, the mixing
motor and the recirculation motor.
The climate control computer also controls the interior temperature sensor.
The sensor and the three motors are connected to the climate control computer by wire connections. The climate
control computer controls the passenger compartment ventilation using a modulated control signal (square pulse
signal) sent to a power module (MVPE) by a wire connection.
All other signals used by the climate control computer or transmitted by this computer to other computers are sent on
the multiplex network.
The production of cold air (cold loop) and hot air (heating) is controlled by the other two computers involved in the
CLIMATE CONTROL function (UCH and engine injection computer).
Special notes on operation:
–When the engine is stopped, the passenger compartment fan rotates more slowly than when the engine is
running.
–If any of the actuators are faulty, the air conditioning can no longer control them, but the setting requests are still
displayed on the control panel: warning lights light up, display of symbols on the control panel (distribution motor
position, passenger compartment blower speed, AC symbol, etc.).
Vdiag No.: 44
MR-413-X44-62B000$230_eng.mif
