when I plugged in my OBD scanner, I got not connected to the vehicle and the dashboard going crazy, and when I unplug the ODB scanner everything going back to normal... the vehicle I am talking about is Dodge Journey 2011, I have problem with the PCM, I bought a used PCM and in order to crank the car I had to input the VIN to new (USED PCM), accordingly I did, and a successful message appeared then the scanner disconnected with the Car and then I tried to connect\ communicate with the car but there was no luck... and then a new thing happened as the tachometer going crazy when the OBD scanner is connected and it back to normal when I unplugged the scanner.... any can help please