i was driving back from hernbay down the a2 when i smelt something funny so i stopped to have a look and the rad had cracked at the top and the fan was running really fast but the temp gauge in the car was fine. i turned it off to let it cool down abit and the fan started to smoke abit and the heating controls stopped working too. i topped the rad up with some water and when i started it back up the fan came striaght back on and the heating controls still wouldnt work but the temp gauge was fine so i drove it home. but this morning when i started it up the fan comes striaght on and the heating controls still dont work but it drives fine the fan is on all the time, has anyone got any idea what is wrong please, i need a new rad (mk4 93 twinturbo auto) thanks