ℹ
info HP
Status LED blinks when receiving data
The machine is currently printing or processing a job; normal operation.
? What Causes This
System activity such as printing jobs in progress.
ⓘ What This Means
No action required. Continue monitoring if issue persists.
Source: page 130 of the official manual
From the manual
This error code appears in:
HP Laserjet Mfp M438