hello! I have the MC2100ELS 50w v1 treadmill board with the U3 IC distroyed, could be STR IC , but can’t read the numbers. There is also a 2w resistance with value of 0,45ohm and a small smd in series , with 1R … can’t read, also a smd transistor Q11. Do you have any schematic diagram? Can’t find anything… Thanks.

 

That appears to be the LV SMPS for the 12VDC power , if so I usually rig up a small mains transformer, bridge and capacitor for the supply , mount it outboard where possible.