help

[PAUL1962]

new hot end fitted all wires are connected correctly started up the machine and all its doing now is going from left to right stopping when it hit the stop switch thing goin back about 2 mill then ro the stop switch etc etc etc i have now left it thinking it will sort it self out but no after 20 mins its still doing it also the hot end isnt even getting warm at all and nither is the heated bed still as cold as they can be

Now afytr having high hopes about building one and pushing the go switch and hoping somthing will print but 3 machines later and 4 hot ends still nothing apart from it bagging it hot end to the stop switch untill you pull the plug

now before i totaly lose it..........am i missing something cause this is driving me mad and has never worked from the start
this is the second machine the company have given me and still no joy I mean REALLY

any help guidence or advice would really be great

thanks

Paul
the machine is a A8 clone with PLA, a heated bed and now a new hot end

[PAUL1962]

would like to add that the board may have blown as the filament is not comming out of the motor so does that mean a new mother board ????