C5 Series II (Facelift) cooling question

Morten · Post by **Morten** » 30 Nov 2008, 20:49

My coolingfans starts to run on highspeed, when the water temp is right in the middle of normal temp. The fans runs for a few minutes and then stops. Sometimes when the fans run, the temp rise to a higher level. Had it checked on a Citroen garage, and they can't find anything wrong with the cooling system.
Anyone else with these symptomes?

C5 2.0i 16V aut series II.

Morten

Post by **CitroJim** » 30 Nov 2008, 21:59

Sounds like the old Bitron Sensor problem that occurs on Xantias and the like. Essentially, if the temperature sensor in the thermostat housing fails open-circuit, the fans run at top-speed as a sort of fail-safe.

I've no idea if it applies to such a late C5 but it will be worth checking the connections to any temperature sensors in the vicinity of the thermostat housing/top hose connection. Anti-freeze can get in then and corrode the connections.

Post by **myglaren** » 30 Nov 2008, 22:28

Sorry to be vague about this but I have heard that a defect in the climate control system can give rise to this problem, either gas pressure too low/high or a fault with the compressor clutch.

Morten · Post by **Morten** » 14 Dec 2008, 19:01

Thanks for the help! I'll check out a few things before I have a chat with Citroen.