Thread: need info on wires going to alternator.

i was just curious as to if anyone could tell me what wire this is for its a small yellow wire with a black stripe that is on the harness for the alternator its a small wire by itsself, i have the ground to the alternator, then the alternator plug then this wire and its not going to anything, anyone know wat it is for or supposed to go to? jw its like always been to nothing just wondered

Its supposed to connect to the body of the alternator by a small 10mm bolt on the back side of the alt. There are 2 small holes depending on the length of the loom for where its supposed to connect.

You can see in this random google image there are 2 smaller bolt holes. the one closer to the top of the picture has got a small bolt still in it.

Imageshack - sale1002ez7.jpg

And if its not for that one (if you have it already connected) then it could be the signal wire for the A/C compressor clutch.

yeah it must be the ac compressor clutch signal, i was just trying to get all my grounds clean and its always been just hanging there and was curious. for some reason i cant get a really good voltage from my alternator, and its a newer alternator too. i see like 13.2 or 12.9 or so volts and cant seem to get a better voltage reading.

Is that the voltage reported by the ECU or at the battery with a multi-meter ?

its the voltage at my turbo timber,i got the apexi pencil auto turbo timer. its weird cause on start up i get like higher voltage then when i drive for a while i get a lower steady voltage like 12.9v. its a newer alt like 500 miles old so im thinking its a ground somewhere or something

Could be bad wiring to the timer then ?

I'd be using a proper meter on the battery or an ecu connection to see what the real voltage is. Accessory eletronics like that could easily mis-report the voltage, although it would be a large error for it to show 12.9 with the motor running, still best to double check with a more purpose built device to be sure.

The voltage will always be higher when you first start the car because the alternator will be pumping the juice back into the battery after starting the motor up.

if it's the wire on the actual connector that clips into the alternator, it goes to your dash gauge to illuminate the battery indicator when your alt goes bad. It needs +12v when running for the alternator to charge.

well i didnt buy the alternator new as the nissan one they wanted like 450.00 so i bought it from a pep buys its a reconditioned one and it was tested before i bought it so i donno.

ive checked basicly everything that i can. ive checked all the grounds and everything but nothing has made any difference, maybe its just not going toput out 13.4v i donno