Casablanca Car

My 2002 jetta 2.0 has a problem with the Alarm Security. It has happened before when i installed a new stereo receiver. It wont start because the fuel pump is getting no power it turns over and gets spark but no fuel . I tested the power at the fuse and the relay and there is nothing there for the fuel pump . I dont know why it happened this time. The last time it happened a friend that does car audio told me a way to reset the ecm and the alarm it was something like turn the key 3 times in the driver doorlock and hold it for 3 seconds . I cant remember what it was and cant get ahold of my friend again. I went to a auto parts store and looked at the well known autodata book and their was only reset codes for lights and mileage issues, no alarm. Does anyone know what to do I just cant beleive that I cant figure this out I have tried everything . I tried unplugging the battery I have a code scanner and the code is p1850 this code says reading problem at ecm.