'MCB' = main circuit breaker?
Or ground fault interrupter? The GFI is in the wall outlet (in the US anyway). It trips if it detects even a small difference in current going to & from the appliance. It's likely your test wire drew away current.
Or else your test wire drew several Amperes? Then it tripped a circuit breaker in the breaker box.
Does the motor run at any time in the machine cycle? If so then the problem could be in the controller.
Do you have a schematic? It makes the job easier although the diagram inside appliances doesn't usually contain enough detail for me to repair it.
Your photographs show several wires around the motor. It is interdependent on the controller and transmission. The cycle goes on 15 to 30 minutes. This makes it time-consuming and tedious to diagnose a problem in a washing machine.