I need the wiring diagram for the stock stereo on the 91 caprice

Here you go.

You only have 4 speakers, 2 at the front (L&R) and 2 at the rear (L&R). What you think might be Tweeters are just for show and don't exist. :>D

1999 Chevrolet Tahoe Car Stereo Wire Colors and Locations

the12volt.com https://www.the12volt.com > installbay > stereodetail
1999 Chevrolet Tahoe Stereo Wiring ; Right Front (-), Dark Green ; Rear Speakers, 6 1/2" Rear Doors ; Left Rear (+), Brown ; Left Rear (-), Yellow.

1999 Chevrolet Tahoe Car Radio Wiring Diagram

modifiedlife https://www.modifiedlife.com > 1999-chevrolet-tahoe-...
Our 1999 Chevrolet Tahoe radio wiring guide shows you how to connect car radio wires and helps you when your car radio wires not working.

How To Chevy Tahoe Stereo Wiring Diagram

My Pro Street https://my.prostreetonline.com > 2018/11/17 > how-to...

Nov 17, 2018 - Using this Tahoe wiring guide, you can wire up anything you need. Quickly identify speaker wires, amplifier outputs and even navigation systems ...
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Orange is Battery Power

2002 Silverado 1500 Stereo Wiring Diagram - The12Volt

https://www.the12volt.com > installbay > forum_posts
Jan 13, 2010 · 3 posts · 3 authors
2002 Silverado 1500 Stereo Wiring Diagram - I'm trying to help a buddy install a Clarion HU in his '02 Silverado. Stock stereo is a CD ...

https://www.google.com/search?q=2002+chevy+1500+radio+wiring+diagram

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Usually red is pos. goes to constant power source. Orange or yellow to keyed power source. Blue is for power ant. and matched wires are your speaker wires. Match these to yours cars wires. Oh black goes to ground.

https://www.modifiedlife.com/2003-chevrolet-tahoe-radio-wiring-guide/

May be an amp trigger wire, Light green, not getting signal back from new stereo. Check against old plug.

This should help you wire up your new stereo. 97 Ranger stereo wiring diagram. They do make a plug in harness for your truck. Metra part number 70-5600.

Check fuse on stereo head unit.

1993 Chevrolet Caprice Car Audio Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Orange
Car Radio Accessory Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Gray
Car Stereo Dimmer Wire: Brown
Car Stereo Antenna Trigger Wire: Pink
Car Stereo Amp Trigger Wire: Pink
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 4′ x 6′
Car Audio Front Speakers Location: Doors
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
Car Audio Rear Speakers Size: 6′ x 9′
Car Audio Rear Speakers Location: Rear Deck
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

pls rate

If the car has a built in amp/s for speakers would need to hook the wire from car amp/s up to amp turn on or power ant from radio