I had a similar outcome with my 1997 XE after swapping the factory stereo out. I still have knob lights, but the recirc and AC switches no longer light up. They still function, just no light.
I just got done swapping my stock head unit out for a Pioneer unit in my 1997 XE and had this same issue. Turns out that, despite NOT having the BOSE system, there is still a factory amp that drives the stock speakers.
The wiring harness I bought to adapt the stock harness connectors to the Pioneer ...