PS5 No Power Case: Bad Power Supply vs. Motherboard Failure
A real diagnostic sequence showing why finding a bad PSU does not automatically prove that replacing it will repair a no-power console.
Case summary
A no-power console initially tested with a failed power supply that was not producing the required 12V output. A known-good PSU was installed so diagnosis could continue. The console still had a motherboard fault: one or more power rails were shorted to ground.

Step 1: verify the power supply
The original PSU was not producing the required 12V output. That is a real fault, but it did not prove the PSU was the only reason the console was dead.
Step 2: substitute a known-good supply
A known-good power supply was installed to continue diagnosis safely. This is where a simple parts-swap approach would have failed: further testing showed that motherboard power rails remained shorted to ground.
Why replacing only the PSU would not have fixed it
A power supply can fail at the same time a motherboard has its own electrical fault. In this case, restoring a valid 12V source exposed the remaining board-level short. The final repair decision therefore had to consider both failures rather than selling a power-supply replacement as a complete fix.
Result
Because the diagnosis indicated extensive motherboard damage in addition to the failed PSU, the console was classified as not economically practical to repair.
