95 Aerostar EXT Airbag issue

[4wilds]

My dad owns a '95 Aerostar EXT and is getting an error code 21. He has had the clock spring replaced, and is still getting the code 21. I did a search here and see that usually it is the clock spring that causes the issue, however with that replaced the only other item I can think of is the Air Bag Control Module but can't find the part anywhere. If anyone has any input I would appreciate it.

Thanks in advance.