Verified answer

The correct radio SERIAL NUMBER is required for a code

First remove the radio from the dashboard.

Then post the radio make+model plus all the letters+numbers on any labels,barcodes and a 14 character Serial Number stamped in the metal casing.

This information can then be used to see if a code can be calculated

you should bypass to the broking service they ought to telephone a code they get from the motorcar utilizing the tech 2 scanner into GM . GM supply the tech a code to punch in to liberate it. no human being else can do it sucks i comprehend .They wish it end theift of their stereos How needs a inventory radio.good success wish I helped GM tech for 20 years