1) Since you have no CV reading at Pad13 it's not making it to that point. The CV goes to many places before finally getting to the VCO's!
a) check CV at R88/R89/R89 junction on mainboard. Put the x0xb0x in Keyboard and play notes manually or just play a pattern. It should be 2V for note C1, 3V for C2 etc.. This is the CV coming from the DAC. If ok go to next step.
b) check CV at Pad Y of the x0xi0 I/O Board. See the pic below. The CV Input goes from the DAC (R88/R89/R90) to the x0xi0 I/O PCB via pad Y. It goes to the switched connection of the CV in jack on the x0xi0 I/O Board so that the internal CV can be overridden by an external CV. If CV is ok at Pad Y go to next step.
c) check the CV at pad Z on the x0xi0 I/O Board. If ok go to next step.
d) next, the CV goes to the Slide Time control on the x0xi0 Top PCB! Check the CV at Pad Z on the x0xi0 Top PCB. If ok go to next step.
e) check the CV at Pad 27 on the x0xi0 Top PCB. This is the CV after the slide time control. If ok go to next step.
f) check the CV at Pin 5 of IC11 on the x0xb0x mainboard. This is the input of the slide buffer after the CV comes back from the slide time control. If ok go to next step.
g) check the CV at Pin 7 of IC11. This is the output of the slide buffer. If ok go to next step.
h) check the CV at Pad 5 on the x0xi0 top PCB. This is where the CV comes back again to the CV Width controls (TM5 & TM402).
2) Once you have CV working then test the VCO's again. Since the noise generator is working I think the problem is just the CV input not connected. If VCO1 and/or VCO2 still not working let me know.