[AccessD] Combo to Combo

I need to create a combo box that lists system identifications. When the
selection is made from the system combo, the 2nd combo only lists
related failures. The problem is the System and the Failure are
repeated. An Alarm can have the same type of failure as a Dryer.

 

How do I set up the tables & the form for the combos to list the Systems
with the matching Failure types when they are all repeated?

 

Example:

System, Failure

Alarm, Age

Alarm, Normal Wear

Alarm, Corrosion

Battery, Overload

Battery, Age

Dryer, Normal Wear

Dryer, Age

Dryer, Obstruction

 

Virginia