ESP8266 Community Forum

I'm testing my first ESP8266 WiFi module https://robotdyn.com/catalog/communication/wifi_module_esp_01_esp8266_8mb/ (with a ESP-01 Adapter, 3.3V, & level conversion)

My question is, after setting the baud rate last night, testing, and getting a good AT+GMR response, it now powers on to a steady Blue LED with no response to AT commands. Only an echo '>>>> AT' of the command sent.

This condition occurs when powered only by outboard 5V power supply, or Arduino.

I have not Flashed the ESP8266.

What could cause this solid Blue suddenly?

I'm testing the module now with Putty.

When connected I get junk characters "▒n▒▒▒nl▒|bl`rl▒▒ՁMEM CHECK FAIL!!!" followed by
MEM CHECK FAIL!!.

Update:
Apparently using AT+IPR=9600 to change the baud rate Bricks the module, and it must be then flashed to resuscitate.

The preferred command to permanently change baud rate is: AT+CIOBAUD=9600. I re-flashed using Ai-Thinker firmware http://wiki.aprbrother.com/wiki/Firmware_For_ESP8266.

After the re-flash everything works.
In the idle state, between commands, all module LEDs are dark.