I need a stereo wiring diagram for 1989 dodge ram truck

SOURCE: need stereo wiring diagram

1998 Dodge Ram 1500 Truck Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Red
Car Radio Switched 12v+ Wire: Red/White
Car Radio Ground Wire: Chassis
Car Radio Illumination Wire: N/A
Car Stereo Dimmer Wire: Orange/White
Car Stereo Antenna Trigger: Yellow
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: Behind the glove box.
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Dark Green
Left Front Speaker Negative Wire (-): Brown/Red
Right Front Speaker Positive Wire (+): Violet
Right Front Speaker Negative Wire (-): Dark Blue/Red
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Brown/Yellow
Left Rear Speaker Negative Wire (-): Brown/Light Blue
Right Rear Speaker Positive Wire (+): Dark Blue/White
Right Rear Speaker Negative Wire (-): Dark Blue/Orange
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SOURCE: 2001 dodge ram 1500 v8 spark plug wire diagram

the firing order is 1 8 4 3 6 5 7 2 clockwise around the cap

SOURCE: wiring and vacuum diagrams

wiring diagrams for a lot of vehicles (but not all!)
go to autozone . com
repair info (on the left)
vehicle repair guides (center panel)
put in your vehicle info
select chassis electrical
then wiring diagrams (on the right, bottom of the list)

You might be able to find vacuum diagrams also, but I'm not sure.

SOURCE: need a wiring diagram

I have a 1990 250 van, you can find a wiring diagram below.
Wiring diagrams for a lot of vehicles (but not all!)
go to autozone . com
repair info (on the left)
vehicle repair guides (center panel)
put in your vehicle info
select chassis electrical
then wiring diagrams (on the right, bottom of the list)