info ADT

Status [0] + [3]

Arms system into STAY mode via single button command without code.

? What Causes This

Single-button arming programmed for ease of use.

What This Means

Ensure the partition is ready to arm and press the correct key sequence.

Source: page 16 of the official manual

From the manual

Manual page 16 — ADT error [0] + [3]

This error code appears in:

ADT Safewatch Pro 3000