ok so my rx300 blows on real low all the time and i cant change the fan but if i play with it for a bit i can get it to go on high for like ten seconds. I first replaced the blower module and it work fine for a day or two than it went out again where is the relay hoping that is bad and not the module again.

 

so went outside and tested somethings.. what I discovered is that when car is in park 3 vents blow hot air one blows cold air (driver side) and I have full controls of heat and ac so. Once I put it indrive is when it freaks out and starts turning of and on, while the car is jerking back and forth kinda thing (gas break gas and turns on in between the two) what could this be??