OBD2 Bluetooth HC05 Arduino

Hello everyone !
I’m trying to get the RPM value from car diagnostic port OBD2 using Bluetooth module hc05 and Arduino, but nothing appeared on serial moniteur of arduino, can anyone tell me where is the problem in my code, Thank you.

ArduiobdconnecetabliRPM.ino (5.77 KB)

You should post your code in the kosher manner, using code tags </>.
Have you checked that the OBD is a plain vanilla SPP device, i.e. compatible with HC-05?