OK, they may have removed the stock radio and amp and had a non stock unit in there with an after-market amp installed. The wiring diagrams for the stereo with an amp and without plus the speaker wire colors is below. With them you should be able to test and see if you have signal at the amp connections in the rear and how to bypass the connector and get sound.
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Thursday, July 27th, 2017 AT 11:06 PM