Help on fault finding on a C3-31 Hammer combination machine

[magicniner]

Break the connection of the braking circuit to the motor and test.

Fault finding is a process of logical elimination, not speculation, the fact that multiple motors suffer the same issue suggests it isn't the motors but it can still be any other common component.

Are the motors single or 3 phase?
I'm sure it's clear on the schematic and DC injection braking is a 3-phase technique but you should post the schematic the right way up and at good resolution if you expect anyone to examine it closely, if you can't be bothered......... ;-)
Regards,
Nick