Essentially, all the wiring required to activate one of those installed phones was included in every W124; to bring the phone live required only to install the handset, transponder in the trunk, and fit the overhead controller. To remove, simply take the individual parts out and leave the wiring in place-it'll do no harm.

I was lucky enough to find a digital version of the phone you're looking to remove, and it took only a few minutes to install it in my '92 500E as all of the wiring's already there. My overhead console memories don't work any more, but the rest of the buttons do!

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo