It will indeed make a difference. vehicles can hold power in them up to 30 min after the battery is disconnected. if you want a fast way to do it, disconnect both positive and negative terminals and touch them together for 30 seconds. this will take all the power out of the vehicle immediately. once you've completed that task, then reconnect the battery, go inside the car and hold the infotainment power button for 10 seconds again. let me know if you get any flashes during or after this sequence!