Data Validation lists and Autocorrections

[Ohrdhor]

Hey guys, I have some drop down lists that currently work as such

Brand A allows you to pick from A1 A2 and A3 in the next cell, which in turn allows you to choose A1X, A1Y, and A1Z etc etc.

however when I want to select a different brand, Brand B, the drop downs then look like Brand B, A1, A1X, and A1 and A1X do not change unless I manually change them

How can I set it up so that when I select Brand B that it will either give me B1, or a blank cell (preferably a blank cell) AUTOMATICALLY?

Thanks in advance guys

 

[Ohrdhor]

Going to bump this thread as i've been waiting all day and haven't recieved an answer