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critical HP

Error Code LED blinks 4 times

Processor thermal protection activated due to overheating or fan malfunctioning.

? What Causes This

Fan is blocked, heat sink improperly installed, or airflow issues in the system.

How to Fix It

  1. Verify that cooling fans are operational and properly seated in the chassis.
  2. Check if the CPU heat sink is correctly attached to ensure proper heat dissipation.

Source: page 54 of the official manual

From the manual

Manual page 54 — HP error LED blinks 4 times

This error code appears in:

HP Prodesk 600 G4 Small Form Factor PC