Unknown alert noise

[Davistosh]

Lock Hi I have a 2005 2.0 hdi desire it has started to make a noise from behind the centre heater vents it sounds like a siren warning it is very irritating has anyone else experienced this it’s intermittent and can sound at any time

[deejay_xb]

check heater fan bushings or dirt accumulated near the fan blades

[oilyrag]

Possibly a door/tailgate switch thinking that the door isn't fully shut? More of a long beep than a siren though......

[deejay_xb]

heater fan is a simple check, just turn the fan off (0 speed) and if the siren sound is still audible then you have other issue..