So I've done a little searching and can't find my answer. Everything I've found says to match up the colors and your good. The swap I'm doing the wires are not an excact match. The recipient is an 87 sr5 pickup. The plug from that has 4wires. It has a black white yellow and red. The donor is a 97 4Runner and that has a three wire plug. It has a yellow with a green stripe and red with a blue stripe and a white wire. I can only assume the black wire isn't used and just match the rest that are the closest in color. Just looking for reassurance on my thoughts before I go a solder them together.

 

Wow Just what alternator do you have on the pick up ??

When new it should have had a three wire plug Red , Yellow and white

the 97 4 runner should have red/blue,yellow /green and white

always fun finding strange modifications with no documents telling just what was done

Before doing anything figure out what that extra black wire is for!!

Why not use the higher output one from the 97??

 

There's always some info I forget to post up. Sorry. I'm using the stock 3.4 alternator and wiring and trying to mate it to the stock 87 pickup wiring harness.

 

Top set of wires are from the 97 and the bottom set are from the 87. I looked through the ewd and I'm not sure what the black wire is for.

 

Well that makes two of us with no clue what the black wire is .

Was the black wire wrapped in the alternator harness ??

Have you checked does it have voltage ??

Does it go to ground ??

I remember a Black ground wire that attached to one of the power steering bracket bolts

Does the original alternator have a round 4 wire plug or just 3 like it should ??

 

 

I'm not sure if it goes to ground since its wrapped up into the harness and I'm not sure how to test it to see if it does go to ground. It is the original harness. Let me know if there is anything else I can look into to help me out on this. Again I'm definitely not electrical savvy