It's a straight swop, you should not even have to resync the key. Make sure the unit is not a 315MHz unit, that will not work. You need to make sure it says 433MHz (to match your key). If you have a high battery discharge, check if the becm is going to sleep, if an auto, see if the red LED next to the P on the gear shift lever goes out after 2mins (switch off ignition and int. lights first), if it still glows dimly after 2mins, becm is not going to sleep. The problems with the rf receiver, are only in certain locations eg airports, garages and possibly other powerful devices at same frequency. If your becm does not go to sleep in the middle of no where its not the rf receiver.