ESP-01 Relay V4.0 Relay Board
ESP-01 Relay V4.0

Available from:


Install method:
USB to Serial

GPIO #Component
GPIO00 Relay_i 1
GPIO01 Led_i 1
GPIO02 None
GPIO03 Button 1
GPIO04 None
GPIO05 None
GPIO09 None
GPIO10 None
GPIO12 None
GPIO13 None
GPIO14 None
GPIO15 None
GPIO16 None
GPIO17 None
Configuration (old format, will be converted to new template when applied)

This works without hardware modification on the v4.0 module, but you can add a switch from RX to GND as an On/Off switch.

How to flash ESP-01(S)

There is no add in for the button on the module as it serves as a reset, rather than an on/off switch.

To make this work with v1.0 of the ESP-01 Relay, you must remove R2 (desolder it or just break it off with a screwdriver) and pull CH_PD high (this is easiest to do with a 10k resistor): https://i.imgur.com/79ySGMt.jpg