I have 5 wires left over. 2 dk. blue and 3 dk. green. The following wire connections I researched and found on a 1998 Bonneville. This is the diagram I am using to wire my Grand Prix. According to the radio vehicle compatibility this radio should work in my 1997 Grand Prix. One of the dk. blue wires is for the right rear audio signal low-level. The other dk. blue goes to the steering wheel control buttons. One dk. green goes to the audio signal right front. One dk. green is listed as fuse out put-retained accessory power and one dk. green is listed as vehicle speed signal-4000 pulses/mile. The diagram I have has a purple/wht wire for LED dimming and I don't have a wire this color. These connections come from the plug that goes into the radio. One is black and the other is gray. I believe there is a white plug that is used and is somewhat different from the gray one I have. It also shows I should have have two gray connections on the black plug but I only have one gray. One goes to the audio signal-l front and the other gray goes to fuse output-instrument panel lights. I only have one gray wire though and I assume it goes to the audio signal-l front. I looked for a 1997 Pontiac Grand Prix wiring diagram but I couldn't find one specific to my vehicle. I very much appreciate your help and patience with me. Thank you, Gary M. Smouse997 Pontiac Grand Prix Stereo Wiring Information
Radio Battery Constant 12v+ Wire: Orange
Radio Accessory Switched 12v+ Wire: Yellow
Radio Ground Wire: Black
Radio Illumination Wire: Brown
Stereo Dimmer Wire: Gray
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue This I found on stereowiringdiagram.info. I have all these wires in my harness plus another dk. blue and two dk. green. My assumption is they are used for add on options such as steering wheel radio control for the other dk. blue. I have no idea what the dk. green vehicle speed signal or the fuse output-retained accessory power are for.
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