Citroen C5 Aircross Quiz
Cooling

General

In this manual: Cooling
AAS - Parking Aid — 8Owner's Manual Citroën C5 II — 139Citroen C5 Aircross (2017- 2024) - Owner's Manual — 143Audio system — 14Overspeed control — 7Multifunction display — 4Driver information instrument cluster — 20Navigation assistance — 8Intruder alarm — 7Mechanical specifications — 9Power supply — 8Electrical equipment — 13Lighting and electrical equipment — 3Immobiliser — 4Sunroof — 10Exterior lighting / signalling — 38Multiplexing — 7Air conditioning — 7Body — 6General specifications — 9Automatic gearbox control — 3Exterior mirrors — 10Airbags — 5Defrost — 6Underinflation — 6Interior lighting — 4Wipers / Washers — 6Window lifters — 11Cooling — 8Opening management — 7Cruise control — 5Suspension — 4Grip management — 1Paint — 2Exterior lighting control — 1Indicators (turn signals) — 1Automatic lighting systems - General recommendations — 1Wiper control — 1Special position of the front wipers — 1
~1min read

Introduction

The cooling function is integrated in the engine ECU (f.R.I.C)

This function controls the engine cooling fan unit during and after engine operation. This strategy is determined according to:

  • engine coolant temperature,
  • requirements from the air conditioning functions,
  • requirements of the automatic gearbox for cooling the automatic transmission fluid (water/oil heat exchanger).

For this function, the engine ECU supplies the following parameters to the BSI:

  • engine coolant temperature,
  • engine coolant temperature warning signal,
  • refrigerant circuit pressure.

The cooling requirement associated with air conditioning is provided by the B.R.A.C. function (Besoin Refroidissement pour l'Air Conditionné, cooling demand for air conditioning), also integrated in the engine ECU. A linear pressure sensor measures the refrigerant circuit pressure, allowing the engine ECU to control the low or high speed of the cooling fan unit. Unlike voltage-level pressure switches, the linear pressure sensor supplies a voltage proportional to the refrigerant circuit pressure.

Capteur de pression linéaire
Linear pressure sensor

Important: the cooling fan unit can run with the ignition off.

COOLING FUNCTION OVERVIEW

Synoptique de la fonction refroidissement
Cooling function overview

Key:

  • Single arrow: wired link,
  • Triple arrow: multiplexed link.
* Selon version

* Depending on version

Principe de fonctionnement : refroidissement

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