mk1focus

hi i have a mk6 2003 ford fiesta 3 door 1.6, when i run it for 10-15 minuets then turn the engine off the fans come on really loud and continue to stay on for a couple minuets then shut off the fans are not on when engine is running and fans turn off when i start the engine back up , this happens without the key in the ignition, the temp gauge says norm, coolant level doesn't move stays on max line, is this normal? or a problem? also smells like a burning rubber smell form the engine bay, any ideas on what this may be? thank you.