Stereo Wiring Harness Question with pics

[soon2bsick]

2002 sport trac, I guess it just has the basic audio set up (not sure what to call it) since it doesn't have the sub/amp combination


I ordered a harness for it which looks like this,

Because all the others I saw with multiple harnesses indicated they were for the amplified systems,

However I pulled the stock stereo this evening and found that there are 2 harnesses attached into the back of it

Can someone please assist me as to what the second smaller plug is and if the harness I purchased will be correct. Or which harness I will need?

Thank you

 

[jrford]

With my '04 that should be a subwoofer connection.
16-pin is power speakers
20-pin rear sound
8-pin Sub on mine.

One of these part numbers might help you,
Metra 70-5521
Metra 70-1771
Metra 71-1771
Scosche FDK13B