B2476 GMC – Cellular Phone Select Service Switch

B2476 GMC Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

B2476 GMC Possible Causes

Faulty Cellular Phone Select Service Switch,Cellular Phone Select Service Switch harness is open or shorted,Cellular Phone Select Service Switch circuit poor electrical connection,Faulty Telematics Communication Interface Control Module

B2476 GMC Description

The OnStar??button assembly consists of 3 buttons: Call/Answer, OnStar??Call Center, and OnStar??Emergency. The Telematics Communication Interface Control Module supplies the OnStar??button assembly with 10 V via the 10 V reference circuit. Each of the buttons, when pressed, completes the circuit across a resistor or set of resistors allowing a specific voltage to be returned to the Telematics Communication Interface Control Module over the signal circuit. Depending upon the voltage range returned, the Telematics Communication Interface Control Module is able to identify which button has been pressed.