When choosing your service center you may want to ask questions about their installation methods and also want to know what days and hours they are open to accommodate convenient scheduling of appointments. You will be surprised to find most service centers are NOT open 7 days a week, or only open 9 to 5 forcing you to take time off work in order to service and install your interlock. With installation methods you want to avoid crimp connections or T-taps, these frequently cause intermittent connection issues and voltage drop that will cause your vehicle to not start, or erratic interlock operation!