If you are getting error 0x5319 with full KDZ, try using mode (available in LG UP patched).
Summary: Error 0x5319 appears when using LG UP (LG’s official flashing tool) to flash firmware on LG phones. It signals a communication or authorization failure between LG UP and the phone (often in Download Mode or when using certain DLLs/CPU-targeted packages). Below is a structured troubleshooting guide, common causes, and step‑by‑step fixes with examples. lg up error 0x5319