Hi! So my girlfriend has a 2004 Impala and she has the radio with the Delphi AM/FM CD only, no aux in and no cassette (also no steering wheel controls, if that's relevant to my questions). In her words, "Who even uses CD's anymore?" She's big on the podcasts and really wishes she could use her phone with her car stereo. I've replaced head units before and my '95 Sonoma and my '86 Cutlass were pieces of cake, even without a harness adapter, but I didn't realize what a headache these Theftlock radios can be.
So I have a few questions. First, I've seen some advice online saying you have to relocate the factory radio to the trunk to preserve the functionality of the little message center in the gauge cluster and this T-harness on Amazon seems to be the way to go (with a slight modification to allow the aftermarket unit to work with the Impala's RAP system). But some people in the original post said you can still reset those lights with a sequence of key-turning and pedal-pressing and you don't actually need to keep the original radio at all. Is this true?
My second question is about the second, small plug in the back of the factory radio. Whether we go with the relocation adapter or just hack directly into the wiring without keeping the original (if that's even possible), I have no idea what those two plugs in that second plug are for and I haven't been able to find out any information about them at all. It's only got two wires going into it -- a green and a black one. What do they do and what should I do about them while installing the new radio?
And, for some reason, my embedded links weren't displaying properly (I'm new to the Impala forums and guess I haven't quite figured out its little foibles), but I got most of my information (and the link to the T-harness adpater) from this post here on the Impala forums from like 10 years ago: https://www.impalaforums.com/audio-v...et-stereo.html