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error HP

Error Code 4 long red blinks

Embedded controller has timed out waiting for BIOS to return from memory initialization.

? What Causes This

System board malfunction or embedded controller issues.

How to Fix It

Consider replacing the system board if software solutions do not work. Contact service provider for precise diagnostics.

Source: page 70 of the official manual

From the manual

Manual page 70 — HP error 4 long red blinks

This error code appears in:

HP Elitebook 840 G4 Notebook PC