Wiring a stereo

It is unlikely the wiring has moved. Here are the wiring diagrams.

1998 Mazda B-Series Car Stereo Wire Colors and Locations

The12Volt https://www.the12volt.com > installbay > stereodetail
1998 Mazda B-Series Stereo Wiring ; Switched 12V+, Yellow/Black ; Ground, Black ; Illumination, Light Blue/Red ; Dimmer, n/a ; Amplifier Remote, Blue.
Front Speakers: 5" x 7" Doors
Constant 12V+: Light Green
Rear Speakers: 5" x 7" Rear Corners
Left Front (+): Orange/Light Green

1998 Mazda B2500 Stereo Wiring Guide

MODIFIEDLIFE https://www.modifiedlife.com > 1998-mazda-b2500-st...
Our 1998 Mazda B2500 radio wiring diagram shows you all the 1998 Mazda B2500 radio wire colors and what they do. Use our 1998 Mazda B2500 stereo wiring guide to ...

1998 Mazda B2500 Pickup Stereo Wiring Diagrams

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1998 Mazda B2500 Truck Car Stereo Wiring Guide; Car Radio Battery Constant 12v+ Wire: Light Green; Car Radio Accessory Switched 12v+ Wire: Yellow/Black; Car ...

Did you bridge the new stereo into the truck using the factory original radio circuit or from another live connection? Does the new stereo have a permanent power wire and where is it hooked up to? Is the battery flat? Trace the wiring mod you have done back to the fuse block and ensure you have left all the factory connections working. Check your fuses and relays so you haven't accidentally grounded a live circuit and damaged something. Best way to go is using an adapter harness like this -
86 93 Select Mazda Ford Mercury Radio Harness to Aftermarket Stereo...

1995 Mazda B2300 Pickup Truck Car Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Green/Purple
Car Radio Accessory Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Light Blue/Red
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: Blue
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 6 1/2? Speakers
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Orange/Light Green
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Car Audio Rear Speakers Size: 5? x 7? Speakers
Car Audio Rear Speakers Location: Rear Corners
Left Rear Speaker Positive Wire (+): Gray/Light Blue
Left Rear Speaker Negative Wire (-): Tan/Yellow
Right Rear Speaker Positive Wire (+): Orange/Red
Right Rear Speaker Negative Wire (-): Brown/Pink

on after market fit radio's the yellow wire is to go to permanent power via a fuse , and the red is to go to ignition live via a fuse and ofcourse the black for the earth no fuse unless connected directly to battery neg terminal

The pink wire from the stereo unit is often the dimmer wire, and is connected to a power feed from the vehicle's side lights. Not all stereos have a dimmer function however, and may not have this wire available.

Hi Welsh, It sound to me as if the constant live feed has not been connected or that the cables have been incorrectly connected. The set is fed with a constantly live connection which is live even when the ignition is off, thereby giving power to the memory circuit. I believe either that has been swapped with the ignition power on, or not fitted at all. Regards John

Check all the fuses to see if they have power. I think the fuse your looking for is in the box under the hood by the battery. I recently had the same problem and had to tap into the big blue wire by the in the car fuse box to get the constant hot to the radio.

Most modern day stereos require a permanent 12v (Red wire) and a ignition live (Yellow wire)

find fuse box, look for radio.
Get repair manual, Kragen, Autozone, etc.

here is the factory harness wires and what they do, recheck thayt it all matches up.

1995 Nissan Pickup Truck Car Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Pink
Car Radio Accessory Switched 12v+ Wire: Blue
Car Radio Ground Wire: Gray
Car Radio Illumination Wire: Red/Blue
Car Stereo Dimmer Wire: Red/Yellow
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Pink
Left Front Speaker Negative Wire (-): Blue
Right Front Speaker Positive Wire (+): White
Right Front Speaker Negative Wire (-): Black
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Light Green
Left Rear Speaker Negative Wire (-): Violet
Right Rear Speaker Positive Wire (+): Blue
Right Rear Speaker Negative Wire (-): Pink
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