HC 05 bluetooth module Not Pairing and not Replying to AT commands

First I thought the HC 01 is damaged. But after some works I got the LED (31) is blinking at a slow rate when 34 is connected to VCC. When 34 is connected to GND/Floating the LED on 31 blinks fast and shows in bluetooth device search in mobile. Sometimes after ~1 minute LED Blinking stops and bluetooth device disappears from search, sometimes it stays longer. When i try to Pair it from mobile(Android) first time i asked to enter PIN and pairing FAILED because of above mentioned disappear problem. After that pairing always fail and ask no PIN.

The module is not responding to AT, commands

There are two ways of activating command mode on these devices. One is to hold pin 34 high as the device is powered on and it should enter command mode at 38400,8,N,1 The other is to hold pin 34 low then set it high after the module has been powered on and it will enter command mode at the pre-programmed speed (default is 9600,8,N,1). The AT commands need terminating with a carriage return/line feed (CRLF). When in AT mode you will need to decide and set the device to be a master or a slave (default) and you should be able to view/change other setting like baud rate, pin, name etc.