I have the original Sony CDX-65RF 10-disc CD player (which includes a display unit, remote control hand-held device, and a "hidden" modulator unit in my car.

Normally, the CD player works when the radio is set to the 88.3 frequency. But now, the system doesn't work. After reading the Sony instructions, I checked the batteries in the hand held remote control, reset the display unit, and made sure the power switch on the display unit was "on". But, I haven't found the "hidden" modulator to see if the power switch is "on" or I haven't traced power to all the wiring because I am reluctant to indiscriminately start removing panels. No diagram or description about the wiring or location of the hidden modulator exists in the original Sony manual and I haven't found one on the internet or in this forum.

Since the CD player and phone already worked through the radio, "communication" between this system and the car should already exist unless it was inadvertently destroyed.

Your help would be appreciated.