That does'nt sound good.
How are you cutting them? Scissors, side cutters?
Is the strip still connected to controller (TH2010 I presume) when you cut them? I ask this because the TH2010 will still have power on the OV and 12V lines when the on/off pushbutton is in Off mode. If you cut it powered up there is every chance you will destroy the TM1809, I don't imagine that the DO line will take kindly to being shorted to either ground or 12V whilst powered up.
How are you soldering/connecting the new pigtails?
Show us some pictures (if possible) and we will try and assist.
Cheers
Odlid Dave