Disabling Deep Sleep mode on Brother Printers

I have a Brother HL-L2375DW Printer which, for the most part, works spectacularly (as far as printers go, at least). They’re relatively inexpensive, the genuine toners are reasonably priced, and they seem to last for years, at least with our relatively light printing duties. I’ve had one consistent issue with it however - network dropouts.

Our printer is connected to the network via WiFi on a dedicated IoT VLAN, and we generally print to it using either PostScript or AirPrint. The printer has a domain name of printer.iot.32kb.net, which is dynamically updated to point to the printer’s dynamic IP address on the IoT VLAN. Occasionally though, the printer would fail to respond, despite it being associated with the wireless AP.

Turns out, this seems to occur when it enters “Deep Sleep” mode. Eventually it will respond, but may take 5-10 minutes. Less than helpful for quick print jobs when you’re trying to leave the house in a hurry!

Turns out that disabling Deep Sleep mode seems to be an undocumented option. Brother says:

NOTE: Deep Sleep setting cannot be turned off, but the sleep mode setting can be adjusted.

This isn’t entirely correct - Deep Sleep mode can be disabled through the LCD Panel settings, though not through the web interface:

1. General Settings

2. Ecolology

3. Sleep Time

   At this point, it will display the sleep time. If you:

4. Press [Back] + [-]

the printer will show a hidden option to disable deep sleep mode. At least for me, this seems to keep it connected and accessible on the WLAN much more reliably.

Further investigation may be required to understand the specific mechanism that’s causing it to become unreachable in the first instance.

Hope this help!