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critical HP

Error Code LED blinks 3 times (failure code)

A fault indication showing system issues detected by HP PC Hardware Diagnostics UEFI when computer does not start in Windows.

? What Causes This

Failure in hardware components while booting into the operating system environment.

How to Fix It

Initiate diagnostics through recovery settings in BIOS and follow on-screen instructions to resolve failures.

Source: page 87 of the official manual

From the manual

Manual page 87 — HP error LED blinks 3 times (failure code)

This error code appears in:

HP Elitebook 850 G6 Notebook PC