I just picked up this 1991 4Runner (3.0v6 5speed) for my oldest who just turned 16 and am going through it fixing what's wrong before she starts driving it. While looking around the engine compartment I discovered this wire on the passenger side of the engine. Anyone know what this is for??

 

A/C magnetic clutch, pretty sure.

 

OK, next question.....where is it supposed to hook up to??

I'm guessing that it goes straight to the compressor. Will have to look at that tonight.

 

It goes to wiring harness, then to A/C amplifier
http://personal.utulsa.edu/~nathan-b.../2aircondi.pdf

However, before you do any work, check to see if the magnetic clutch is working, so you know if it is worth chasing for you or not. Jump this wire to a 12 volt source, see that center part of ac compressor pulley starts to spin. If it does, don't leave it for more than a couple seconds. I don't think it's healthy for the compressor to run dry.

 

Found the other end of it last night so I'll hook it up and check things out as soon as I get the knock sensor replaced.

 

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