AT Commands Not Working for HC-05 Bluetooth Modules

Hello, I am trying to connect two HC-05 bluetooth modules in a master-slave configuration. I cannot get the AT commands to show on my serial monitor. I've looked at multiple forum posts and various articles and did the following: uploaded a new, empty sketch to my arduino which is connected to the bluetooth module with the rx and tx pins disconnected, set the serial monitor to both nl and cr with a baud rate of 38400 and entered the command "AT" without the quotes. Just in case the baud rate was set improperly for some reason, I tried doing the same commands with the different baud rates available on the serial monitor but I still do not get any output. How do I get the AT commands to work to pair my two bluetooth modules? Or is there any other way I should pair the bluetooth modules?

I'd appreciate any help!

Note that the HC05 inputs (RX and EN) are not 5V tolerant. If they were connected directly to 5V there is a chance that the HC05 has been damaged. Be sure to use the level shifter on the RX pin and never connect EN to any voltage above 3.3V.

This page may be of interest:
https://www.martyncurrey.com/arduino-with-hc-05-bluetooth-module-at-mode/

The procedure in my tutorial has helped me and some others to get their HC05 units into AT mode for setup. It uses the lessons in the page linked above along with some tested code and wiring.

My HC-05 is connected to the 3.3V pin in my Arduino and the light on the module is blinking I think one flicker/2 sec so wouldn't this indicate the bluetooth module is working? I think I'm just having trouble getting the AT commands to show up since I don't get any response or an "OK" after entering "AT"

Is your HC05 marked "Power: 3.6 - 6V" If so, it needs 3.6V minimum to operate. Connect the HC05 Vcc to 5V.

2 seconds on and 2 seconds off means in AT mode.

How are the HC05s wired to their respective Arduinos? Please post schematics.

Photos of the wiring are often useful, too.

Please post your test code.

Please read the forum guidelines to see how to properly post code and some information on making a good post.

Use the IDE autoformat tool (ctrl-t or Tools, Auto format) before posting code in a code block.

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