So I have a 1990 mustang that had the football shaped amp from the factory. It was removed when I added an aftermarket radio. I've had 2 aftermarket radios installed by 2 different audio places over the course of 20 years. The 2nd one has been in for 12 years along with amp and sub wired to the hatch cargo area. I'm about to install a flip out radio with gps so I went in to see what wiring was done back in the day.
1. There are 2 rectangled plugs and 2 grey square type plugs. The rectangled ones are black and grey. From what I've read black is supposed to the speakers and the grey is constant power, ignition, antenna etc...
The 2 square grey plugs I believe are the amp wiring, amp power and the other plug is more speaker wiring from the amp.
So I went ahead and bought the radio harness plugs that are the 2 rectangled plugs cause i was at best buy and thought since i was there I'd go ahead and pick it up to do it right.
The wire chart here shows the speaker wire on bottom-the black connector and the upper part is the grey wire chart. These connect "TO YOUR HARNESS" from the headunit plug wired in.
Then when i got inside the dash i found the black one not being used and the grey one tapped into-2 wires only and the speaker wire hooked up to one of the square amp plugs. So now I have a new wire harness I cannot use cause they are not being used now, unless I want to go deep into this project. I will probably just take the harness back.
This is the already installed headunit wire information that is the very small plug in the upper pic, lower right.
Hard to see in the pic cause I cut it off but the lower square plug is NOT being used, wires are cut and capped, the end plug one on top is the one BEING used, it connects to the connector where my blue screwdriver is pointing. Then the speaker wire runs to the very small head unit plug.
So as I'm seeing this I'm really thinking i will leave it how its wired because the sub and speaker wires are working fine and I've had no issues with that plug in 12 years. So looks like i will will tap into those from the wire harness of the headunit already installed when the new radio arrives. So as it sits, i will just tap into the constant power, ignition etc cause its really easy to decode with the one already installed. I will never sell the car so i'm cool with it. But maybe this can help someone else if they go in and find jacked up wires, so it can be wired in this way and mine has been this way for 12 years, hope this helps some one else.
1. There are 2 rectangled plugs and 2 grey square type plugs. The rectangled ones are black and grey. From what I've read black is supposed to the speakers and the grey is constant power, ignition, antenna etc...
The 2 square grey plugs I believe are the amp wiring, amp power and the other plug is more speaker wiring from the amp.
So I went ahead and bought the radio harness plugs that are the 2 rectangled plugs cause i was at best buy and thought since i was there I'd go ahead and pick it up to do it right.
The wire chart here shows the speaker wire on bottom-the black connector and the upper part is the grey wire chart. These connect "TO YOUR HARNESS" from the headunit plug wired in.
Then when i got inside the dash i found the black one not being used and the grey one tapped into-2 wires only and the speaker wire hooked up to one of the square amp plugs. So now I have a new wire harness I cannot use cause they are not being used now, unless I want to go deep into this project. I will probably just take the harness back.
This is the already installed headunit wire information that is the very small plug in the upper pic, lower right.
Hard to see in the pic cause I cut it off but the lower square plug is NOT being used, wires are cut and capped, the end plug one on top is the one BEING used, it connects to the connector where my blue screwdriver is pointing. Then the speaker wire runs to the very small head unit plug.
So as I'm seeing this I'm really thinking i will leave it how its wired because the sub and speaker wires are working fine and I've had no issues with that plug in 12 years. So looks like i will will tap into those from the wire harness of the headunit already installed when the new radio arrives. So as it sits, i will just tap into the constant power, ignition etc cause its really easy to decode with the one already installed. I will never sell the car so i'm cool with it. But maybe this can help someone else if they go in and find jacked up wires, so it can be wired in this way and mine has been this way for 12 years, hope this helps some one else.
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