CDR-210 to CDR-220
 

I found a good deal on a Becker CDR-220 radio so I figured I would replace the CDR-210 that is currently in my Boxster with the CDR-220 so I can use the CD changer function to run a plug to my iPhone so I can play music from there.

It turns out that the body of the CDR-220 is slightly wider than the CDR-210 and won't fit in the CDR-210 mounting cage that is in the car. Do I need to find a mounting cage for a CDR-220 or if I simply remove the cage, will the radio latch onto the plastic? Any guidance is appreciated!

OK, so I figured out that I simply need to remove the CDR-210 cage to get the CDR-220 radio to fit (simply slides in once the cage is removed). I'm now working through two additional issues:

1. SOLVED: I previously entered the incorrect radio code too many times and the radio now displays "WAIT". I've read that leaving it on for 30 minutes resets this but this didn't work in my case. Anyone know how long it takes to reset the radio? Update - I let the car sit for an hour and then let the car idle again for 15 minutes and it reset. I was able to enter in the code and get it working!
2. The CDR-210 has a ground lead on the cage. I disconnected this wire and grounded it (to the large brown wire in the radio harness). My car now honks once when I lock the doors. All the trunks, center console, etc. are shut so I've got to imagine that it is the change in radios. So I'm suppose to run that wire from the cage to ground, right?

If you don't ground that wire, you won't have the beep. I have an aftermarket stereo and left the wire hanging, no beep.

Wow - you are right! Funny, I was reading the Bentley book and it indicates to ground the wire. I grounded it and when I lock the car I get the single beep. When I didn't ground the wire, the beep goes away - thanks!

The single beep is normal; it confirms the car is locked.

Not on mine. Mine only beeps when there is something not ready, ie glove box, console, trunk, frunk or top not secure. If all secure the car locks and the the flashers blink twice to confirm.

My understanding is the same. When you lock the car, if it honks twice there is an issue but if it honks once, something is open still. In my case a faulty ignition switch was causing this to give false reports - which drove me crazy!