Citroen C5 Aircross Quiz
Underinflation

General

In this manual: Underinflation
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
3steps
~18min
2/5difficulty
Done 0 of 3

PREAMBLE

The underinflation detection function provides the following information to the driver:

  • abnormal tyre pressure condition on the vehicle,
  • number of tyres not being monitored.

The following components make up the underinflation detection function:

  • a pressure sensor combined with an RF transmitter, fitted in the inflation valve (on each tyre),
  • an RF receiver integrated into the steering wheel switch module,
  • the BSI, which compares the pressure information received with preprogrammed thresholds.

Messages specifying the nature of the warning are displayed on the multifunction screen.

BLOCK DIAGRAM OF THE UNDERINFLATION WARNING FUNCTION

Synoptique de la fonction avertisseur sous-gonflage
Block diagram of the underinflation warning function

Triple arrow = Multiplexed link

LE MODULE EMETTEUR

THE TRANSMITTER MODULE

Le module emetteur
The transmitter module

Key:

  1. Sensor-transmitter electronic unit,
  2. Inflation valve,
  3. Sealing gasket.

All four tyres on the vehicle are fitted with transmitter modules.

To withstand vibration, the electronics are encapsulated in resin.

Power is supplied by a lithium battery with a service life of approximately 10 years, allowing autonomous operation.

The transmitter modules are fitted with an inertia switch comprising a ball and a spring.

Using the centrifugal force generated by tyre rotation, the inertia switch detects whether the vehicle is stationary or moving.

These modules transmit a radio signal at a frequency of 433 MHz.

The integrated pressure sensor is piezoresistive.

STEERING WHEEL SWITCH MODULE

The steering wheel switch module is a single-piece unit comprising the following elements:

  • combination switch housing (1),
  • clock spring (2),
  • wiper switch (3),
  • audio system control (4) (depending on version),
  • cruise control switch (5) (depending on version),
  • lighting switch (6).

The steering wheel switch module provides the human-machine interface for the following controls:

  • radio,
  • cruise control,
  • wipers and lighting.

The steering wheel switch module transmits the user's actions to the BSI via the VAN CAR 1 multiplexed network.

The steering wheel switch module also performs the following functions:

  • controlling the buzzer integrated in the instrument cluster housing according to sound requests sent by the BSI,
  • receiving RF messages from the plip and the tire underinflation transmitters,
  • communicating with the transponder for the coded immobilizer,
  • transmission of information from the steering wheel angle sensor.

Module de commutation sous volant de direction
Steering wheel switch module

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