Fan not spinning faster when high temperature load
Hello guys, my macbook pro 13" mid-2012 has like 96°C temp under load (HWmonitor reading) but the fan stay at 2000rpm (smc fan control reading). Smc fan control show 80°C (lower than HWmonitor) and the fan still don't spin faster than 2000rpm. And when it's very hot in there, HWmonitor shows temperature alarm with cpu at 94°C and GPU at 96°C, fan still at 2000 rpm. I can manually put the fan at 6200 rpm with smc fan control and istat menu, and then the temp get lower (i have cleaned the fan and the radiator, there's no dust). There's no more automatic spinning fan management.. What do you think it is? Motherboard problem? Am on yosemite and have tested it on mountain lion fresh instal (just one time the fan did gets at 2500 rpm under ML during a test watching a 4K 60P youtube video).
MacBook Pro, OS X Yosemite (10.10.5)