DTC B2476: Cellular Phone Select Service Switch Malfunction - Radio: Description

If voltage signal received from 3-button OnStar(R) assembly is not within 2.8-3.2 volts, Radio Interface Module (RIM) inside radio will set DTC B2476. RIM monitors reference voltage from 3-button assembly every 300 milliseconds when radio is on and ignition is in RUN or ACC position.

When DTC B2476 is set as a current code, RIM will ignore all inputs from the 3-button OnStar(R) assembly. DTC B2476 will clear when conditions for fault no longer exist or when scan tool is used. A history DTC will clear after 50 consecutive ignition cycles if conditions for fault no longer exist.