Air filter fit side

[Annddrriy]

If I turn ignition on than 12V goes to windshield bottom grill without turn front defrost button ?

[shogun]

You have to try it and test. I assume the windshield grill element will only start after the engine has been started, so that there is full power to the motor starter first. And only when the outside temperature is below 5 degree Celsius the windshield heater will work. And as that is controlled by the IHKA control module via the relay, the IHKA must be switched on probably.
Try to study the wiring diagrams more in detail.