Yes it can.
Sure, connect anything to the battery that will use power.
i have a 95 mercury grand marquis how do i remove the passtime device You should NOT unless you paid off the car. the dealership will then remove it.
All electrical devices create at least some amount of drain on your car's battery. Although the amount will vary by device, a properly wired system will charge via the car's alternator with no adverse effects.
You can not bypass the passtime. WARNING: if you have passtime and bypass it and the dealer finds out you did they can and most likely repo the car and not refund your money. you signed a contract for passtime when you bought the car.
If the car is on (Ignition is on, engine is running) then no. Nothing should drain the battery when the car is running, there is a device called an alternator with a belt that usually goes around the crankshaft that transforms the mechanical energy into electrical energy. As long as you have the car running, the battery should not die. If so, you have a mechanical problem.
A car battery in any car would drain due to a short in the electrical system.
If the ashtray light is not working it will not drain the battery.
You can get a car alarm that uses it's own battery so wont drain the car.
A starter does drain a battery. The battery holds a charge so that you can use your starter to start the car. After the car is started the alternator recharges your battery and runs your car and all it's accessories. If your car won't start or is having a hard time starting you can drain your battery by repeated unsuccessful attempts to start it.
If the alternator is installed incorrectly, yes, it can drain the battery.
Yes, if the relay was stuck it would drain the battery.
leaving on the radio