206 heater blower/electronic panel problem

[p45man]

hi all i have a 2000 206 gti, and i have just fitted a new heater blower motor as the old one just blows full blast, the new one works in a fashion after about 10 seconds after starting the engine it just slows and then stops which is what the old one was doin until it just starting blowing full,

Im thinking it may be the panel whch is faulty or maybe the heater blower motor resistor (which peugeot seem to have hidden) as anyone come across this problem before!!!!!