Can rear window discharge battery?

[Dusan]

First of all I wanna thank to ericthecarguy for helping me finding the problem of discharging battery in my car (Opel Zafira)! Using “How To Perform a Parasitic Draw Test – EricTheCarGuy” on youtube I founded where is the problem – it is electric lifter for rear two windows.
Now, my question is – how is it possible that some electrical component on car can drain battery when it is not a part of “live” electrical circuit (like radio, alarms, etc…)?

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[college man]

are you refering to the rear defogger? a load such
as a rear defogger needs to be energized to cause a
draw.either something is stuck on or wired direct.

[Dusan]

No, the problem I found is on the electric window of backseat door (not on the defogger). Can it be “active” (in some way) even when the car is off?

[Dustin Hicks]

[quote=”dusan” post=52447]No, the problem I found is on the electric window of backseat door (not on the defogger). Can it be “active” (in some way) even when the car is off?[/quote]

Yes. Look for switches and relays that aren’t opening completely. Also look for frayed/chafed wires. (Bad wiring is most probable.)

[college man]

anything is possible. you would think if it was
active it would move or burn. if you suspect the device.unplug it
and see if the symptoms go away.

[EricTheCarGuy]

It depends on the vehicle. Some vehicles use control units to raise or lower the windows during start up or shut down. If this is the case then they can be active with the key off. It really depends on the vehicle and how it’s wired up. This is why I say finding a wiring diagram is so important when dealing with electrical issues. They are the road map that will lead you to the solution. Without them, you’re driving blind.

[Author]

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