No, just turn the ignition on. Don't start the car.
Keeping in mind that keeping ignition on drains the battery, try to switch the daytime running lights off, switch radio off, music off...
Other reason to keep the engine off is that running engine produces heavy RF noise which might affect the coding signals if the system is not properly grounded and shielded.
Last edited by April1; 11-10-2012 at 05:48 PM.