Alpine CDE-123 Questions

[PatHastings]

I am able to pick between Auxiliary and Aux Rear, but there doesn't seem to be a plug for it. Not really sure why they would give you the option if there is no hardware for it.
anyone know the reason for this?
Thanks
-Pat

[keep_hope_alive]

the KCE-237B connector which gives you a rear AUX input. your owner's manual describes this on Page 19