Citroen C5 Aircross Quiz
Air conditioning

Auxiliary burner

In this manual: Air conditioning
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
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Performance

The auxiliary burner is intended to improve the warm-up of the vehicle cabin.

Heating is provided by a diesel-fuelled burner that heats the engine coolant circuit water. The burner is located in the engine compartment.

Functional description

The auxiliary heating request is managed by the BSI.

The auxiliary burner is controlled by the engine ECU.

The BSI generates the auxiliary heating request based on the following information:

  • engine coolant temperature,
  • Outside temperature (from the passenger-side mirror sensor).

Activation and switch-off of the burner are defined by the following 2 thresholds:

  • activation threshold: engine coolant temperature < 74 °C,
  • switch-off threshold: engine coolant temperature > 79 °C.

Note: The burner is only controlled if the outside temperature is below 10 °C.

The BSI then sends the auxiliary burner request to the engine ECU via the CAN network, according to the table below:

Nota : L'information moteur tournant est indispensable pour activer

Note: The engine running signal is required to activate the burner.

Switching off the engine immediately cuts outputs CA1 and CA2.

Activation / switch-off delay of the auxiliary burner

Activating the burner

Note: When the engine running signal appears, the BSI starts a 60-second stabilisation delay before the heater resistors are switched on.

Cas de l'activation du brûleur

Switching off the burner

Cas de la coupure du brûleur

Burner switch-off in case of impact

In the event of an impact, the airbag ECU sends the BSI a signal that a pyrotechnic element has been triggered.

The BSI immediately cuts the power supply to the burner.

Degraded modes

The degraded modes for the auxiliary burner are as follows:

  • Outside temperature information invalid: activation of the auxiliary burner is prohibited,
  • Engine coolant temperature information invalid: the auxiliary burner activation request is based on the outside temperature information, simulating an engine coolant temperature of 40 °C.

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