2004 Pontiac Montana Stereo Wiring Information
Radio Battery Constant 12v+ Wire: Orange
Radio Accessory Switched 12v+ Wire: Yellow
Radio Ground Wire: Black/White
Radio Illumination Wire: Gray/Black
Stereo Dimmer Wire: Brown
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
2004 Pontiac Montana Speaker Sizes
Audio Front Speakers Size: 6 1/2″ Speakers
Audio Rear Speakers Size: 6 1/2″ Speakers
The following information is currently not available:
Stereo Power Antenna Trigger Wire
Stereo Amp Turn-On Trigger Wire
Audio Front Tweeter Size
Audio Front Tweeter Depth
*If you know any of the above or any other missing information please use the comment box below to notify us.
Why the Radio Accessory Switched 12v+ Wire / Left Rear Speaker Negative Wire (-) is the same color (yellow)
Stereo Dimmer Wire /Left Rear Speaker Positive Wire same color (brown)
Why the radio acc.sw.12v wire/left rear speaker negative (-)
wire is the same color (yellow)
Stereo dimmer wire/left rear speaker positive wire
the same color (brown)
The switched 12 positive “yellow” as they referred to it in the diagram is really the PINK wire.
The grey/black wire is the dimmer wire
I have also noticed that the color brown and yellow wire are both voltage / wattage.
In a short brief****
Using a ohm meter/voltage
Use a vehicle negative ground and the positive probe on the brown wire while the lights are on the vehicle and adjust the lights with the dimming switch your meter should show you a variable voltage very low they’re very high as you turn the switch.
This is your voltage switch wire
Repeat the same process for the color yellow.
Speakers have a ohm resistance 4ohms 6ohms or 8ohms at the speaker/source.
Set your meter to ohm 10th plc
Use your meter in check for the impedance of the speaker.
Now you know what wire does what
That’s what I have to do to my Pontiac Montana 2004 is that procedure..