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1988 Honda Prelude Repair Question


Topics covered: Alternator, Electrical system.
Mileage: 240,000 miles.

Asked on May 19, 2012

What do the wire colors on alternator wire harness mean ?

Took my jdm 3 pin alt plug off harness and spliced a 4 wire usdm(i think) plug to harness...wire colors on my harness are black/yellow...blue/white...and green/white...those wires match up so i spliced those to the plug, but there is extra red/white wire hangin...what do i do with it? what do the colors mean and what is their function? I didnt have the money to buy an oem alt from parts store so im trying to work with what i got ?
Avatar Asked by king8657

Answer

Replied on May 19, 2012

It goes back to the computer-see below

Tiny Answered by rasmataz
68 questions asked
Replied on May 19, 2012

so on my carbed prelude will this alternator work? if so then where should i connect or splice the extra red/white wire to make it work? should i just leave it hanging?

Tiny Response from king8657
4 questions asked
Replied on May 19, 2012

You can ignore it-and check the running voltage of the alternator if its correct

Tiny Answered by rasmataz
68 questions asked

Replied on May 19, 2012

on my other post about this problem they said it wont work....so will the fi alt still work on my carb prelude?

Tiny Response from king8657
4 questions asked
Replied on May 19, 2012

The wire you refering to goes back to the computer as indicated in the picture which controls the alternator's field generation circuit-

Tiny Answered by rasmataz
68 questions asked
Replied on May 19, 2012

so will it work without that wire plugged into anything

Tiny Response from king8657
4 questions asked

Replied on May 20, 2012

As mentioned in the earlier question, it will not work as designed, i feel that it will do one of two things, not work at all or go to an over charge state, which can do serious damage to electrical systems, the colour coding is just to distinguish which wire goes where on the schematic, i would suggest that you get your old alt overhauled and avoid the possibility of doing any damage.

Tiny Answered by mhpautos (expert)
26,882 answers provided