Can't find electrical short

Working on a Goodway/Yama Seiki GS 4000 with a Fanuc Oi control,
Having a problem with an electrical short on the 24 volt dc side that I cant seem to locate , I have noticed on two other Goodway machines, on the main relay circuit board, the 24 volt dc circuit wires 5+ and 6- where they plug into the main relay circuit board, there is discoloration on the board as if these wires became very hot at one time, the Goodway/Yama Seiki machine I’m working on now, has this section of the relay board burned (short circuit), this circuit starts from the transformer 24 volt ac and is wired to a dc rectifier, then wired to a capacitor and then wired to a large resistor, from here it is finally wired to the relay board as 24 volt dc power for distribution, this 24 volt circuit, wire 5+ and 6- are distributed throughout the CNC electrical system, has anyone experienced this issue and what was the most likely cause of this short circuit, all other Goodway/Yama Seiki machines located here have the same 24 volt ac to dc configuration, this is the first time I have worked on a Goodway/Yama Seiki machine, I did not mention, I have no electrical prints on this machine,

The good news is that with an working machine you can make comparative measurements, the bad news is that 24VDC goes to a LOT of places.
I would pull the output from the (the transformer 24 volt ac and is wired to a dc rectifier, then wired to a capacitor and then wired to a large resistor) = low budget power supply and measure the resistance on the OK machine, and the Not OK machine.
That should give you an idea as to what normal is. Try to unplug 24vdc items on the bad machine until an reading close to the good machine is found.
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If not send me an PM with your E Mail and I will send you one (Monday) from our GS240, not the same but at least something.

Consider that the discolored terminals may be the cause rather than a symptom. THe discoloration on the other machines could mean that the connector is overloaded and under normal conditions heats up. Eventually this causes oxidation, which creates resistance and more heat until it fails.

I could be wrong, but simply replacing this section of the circuit is a good start

Is the 24 volt system a simple daisy-chain or a more complex network?

If it's a daisy chain, I'd start with an attempt to localize the fault through directional resistance checks. Pick a point halfway through the daisy-chain and separate it. Measure the line to line and line to ground resistance on either side of the broken daisy-chain. If either side has an egregiously lower resistance than the other, then you know which direction the fault is likely in.

Wash, rinse, repeat until you find the culprit.

This technique works with more complex, messier circuits too as long as you are able to trace the wiring effectively.

Though it's not always 100% reliable when control elements are involved. Sometimes the fault is on the load side of a normally open control element and can't be picked up in this manner.

One other question. Are you sure it's a short? Discoloration from overheating is usually indicative of an overload or high resistance connection rather than short circuit or ground fault. The latter usually leave burn marks, spatter and smoke residue rather than discoloration alone. Does the machine run normally? Or does it crash immediately on startup?

It could also simply be a design flaw if the board was not engineered correctly to handle the load placed on it by the machine if there are other instances of this happening.

Can you beg, borrow or steal an IR camera? Might reveal the problem, or the wires leading to the problem.