Bypass diode replacement

Bypass diode replacement means swapping out a failed bypass diode in the module junction box. The sources say this is technically feasible. It is a corrective action for Bypass Diode Failure. Diodes usually fail in one of two ways: open circuit or short circuit. Before replacing a diode, confirm the fault by testing it directly with a multimeter in diode or ohmmeter mode. This is the best way to tell whether it is shorted or open. The recommended repair is to replace the affected modules or qualified diode assemblies, fix any upstream mismatch or shading, and then check string behavior after the repair. In practice, operators usually replace the whole module rather than just the diode. Modules with a failed diode that are not replaced should be closely monitored. Open-circuit diodes are hard to detect and normally go unnoticed unless the module has significant mismatch, so some failed diodes may never be found and replaced. Avoiding partial shading extends bypass diode lifetime and lowers the chance of further failures.

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• sentence 3: support check: partial - Multimeter testing as best way to identify short or open is stated, but a 'before replacing' confirmation step is not explicitly stated.
• sentence 7: support check: partial - Passages say open-circuit diodes are hard to detect and normally not detected absent significant mismatch, but 'never found and replaced' is an inference.
• sentence 8: support check: partial - Passage says avoiding partial shading extends bypass lifetimes, but not explicitly that it lowers chance of further failures. -->