There are only a few spots that affect both bypass and effect mode. You must not be getting signal in one or more of these connections; I would reflow the solder in these spots and/or use a multimeter in continuity mode to test the connection between each of them:
1. From the input jack to the the IN pad on the PCB
2. From the eyelet marked 4 to lug 4 on the foot switch
3. From lug 8 on the foot switch to the eyelet marked 8
4. From the OUT pad of the PCB to the output jack
It may be helpful to look at the pink lines in the diagram below. (But it may also
not be helpful, so don't sweat it if that's the case!)
You can read about mechanical bypass switching in detail in
this excellent thread by Stephen.