Why 5 wires to each stock rear speaker?

[forestdan7]

Does anybody have a wiring diagram for an 87 4Runner? (Saving for the FSM right now.) I'm finally stripping the cargo area to address some rust, and pulling the stock rear speakers, there are two connectors going in, one with three wires, one with two.

Two on each side are obviously pos and neg for the speakers. But what about the other three? Are these speakers powered/boosted somehow? All lights, etc., seems to work with both connectors on each side unplugged.

PO had aftermarket speakers hooked up with the pos and neg wires (just cut the stock two wire connector off), but left the stock speakers in, with the three wire connector plugged into the stock speakers.

Thanks.

 

[fourwd1]

The FSM shows exactly what you describe. The 3 wires go to a box attached to the speaker. Diagram doesn't say what it is, but might guess would be an amp.

My 84 Runner doesn't have that. My 89 might, but it's to cold to pull the whole panel off to check, sorry.

 

[RedfishBluegrass]

When you hook up an aftermarket stereo in that truck, the easy way you end up cutting out the factory amp, and the speakers on the sides but not the two top tweeters in the back. See if this helps, 87 Pickup stereo wiring diagram - YotaTech Forums. If not do a search on yotatech in the electrical section, tons of diagrams. Good luck!

 

[forestdan7]

Thanks you all. Much appreciated. That site is really nice. I'm going to rip out all the crappy wiring the PO did and start over.

Figured it was an amp of some sort. I'm thinking I'll just pull the speakers and amps, and replace with some small speakers in the stock location. I'm not big on the bass anyway.