T350 Cooling fan stuck on.

[martin996uk]

Hello all. I've been for a run today and when I parked up and took the key out, the nearside cooling fan kept running. I waited about 10 minutes but the fan just kept running. Surely this isn't right. It has never happened before. It will probably drain the battery eventually so I disconnected the fan. Any ideas what's going on? Maybe the thermostat has had it.