bostonspgs

iTrader: (1)

so i am rebuilding my wiring harness and figuring out what is needed and what isnt (someone tried this before and hacked and left). so right in the middle of the fem 02 clip there is a brown wire that runs just past the turbo on my s4 where it is cut and taped off. im pretty good with schematics but my prob is i can find the wire in the schematic but not where it goes.
you can see the wire im talking about on page 50-117, 50-38 in the fsm. i would upload it but i cant figure how to cut from adobe
thanks

satch

iTrader: (1)

Front side of harness goes to the Circuit Opening Relay. Bottom left of page 50-31

HAILERS

The EM side of that wire goes to the fuel switch inside the afm on a series four. It's also spliced to the fuel pump check connector. Jumper the fuel pump check connector and it does the same thing the afm vane does when moved aft.........puts a gnd on the circuit opening relay. Done Page 50-25 of the 88 wiring diagrams online.

bostonspgs

iTrader: (1)

yah ive been trying to word it properly as the wire you pointed out before editin goes the wrong way that this wire comes out buy the circuit opening relay,lol but youve just verified where it does go so ive been writing and deleting for nothing and only confusing myself. thanks guys i do appreciate it.

bostonspgs

iTrader: (1)

okay i think i found where this wire goes seeing as how the wires that i should prolly mention the size diference the wire im looking at is 18g there is also a black wire that is cut right around the same area. the wire goin to the afm is intact and 18g aswell but runs parrallel to(not with) this wire. so my assumption is this(these) wires must go to the fuel pump circuit terminal but as i cant find that on my car i was wonderin if you might have a pic of that .btw black ground comes from the engine block opposite direction from the brown wire

satch

iTrader: (1)

https://www.rx7club.com/attachment.p...4&d=1268002655
Overabundance of arrows provided by Hailers

The Black wire depicted in the pic I provided (post #2) would be the ground for the fuel check connector and grounds to point #24 which is illustrated in the lower right part of the last page of the wiring diagram document. If the Black wire you came across is one in the same with the wire in the diagram then this wire connected to the Brown wire will cause your fuel pump to turn on with the key to "on."

bostonspgs

iTrader: (1)

well there isn a connector there on mine not that there wasnt but its gone now . and my fuel pump works thats not a prob its the amount of cut wires that im not positive where the go if not needed i remove all the way to the ecu and unplug but some of the systems are better stock than hacked like they are

bostonspgs

iTrader: (1)

so that is not what this brown wire is for , im still not sure what it is for but the wire at afm and at the relay is different , ran test to see if its the right wire and it isnt ill try to put some pics up in a little. hailers i am in need again

satch

iTrader: (1)

I'm sure you didn't because you would do something like that but I'll ask anyway. Did you make sure you didn't confuse a Brown wire with Brown/White?

bostonspgs

iTrader: (1)

nope its solid brown here is a pic open harness by turbo ,ahem as i made this i found this brown is tapped off the afm wire so more over now we know what it comes from , where does it go?<edit i know where it goes ,now , but what is the fuel pump circuit terminals function , lets assume my car ran before without it , its gone should i replace? or remove the tap and the ground

bostonspgs

iTrader: (1)

okay never mind that last post , i never noticed the tap in the wire. is it necessary to put the fuel pump circuit terminal back ? what was its point

satch

iTrader: (1)

Are you referring to the fuel check connector or the fuel pump relay resistor?

If it's the former then it's used to check for fuel leaks after you worked on the engine as a safety check. It's also used to diagnose problems with the fuel delivery system, testing fuel pressure and so on. If it's the latter then it's used to change the voltage seen at the fuel pump.

bostonspgs

iTrader: (1)

well this is under the hood right now , all i have there is the br and b/w wires no relay or resistor green and yellow in second pic , variable resistor is intact

HAILERS

I answered your question in post number three above as to what the brown wire goes to and does.

Brown wire causes the circuit opening relay to pull in if the afm vane moves aft and also does the same job if the fuel pump check connector is jumpered. Pulling in the circuit opening relay causes the fuel pump to run. On a series four the pump does not run by just putting the key to ON. It comes on only if the key is HELD to START or if the engine actually starts and pulls the vane in the afm aft............................or if the fuel pump check connector is jumpered to simulate the vane moving aft.

The check connector is there so a mechanic can make the fuel pump run when checking out leakage on the fuel rails etc without starting the engine. See FSM fuel and emissions section.

bostonspgs

iTrader: (1)

there is no connector as in none at all cut wires taped as originally stated , maybe im wording this wrong but the pics should show why i am inquisitive as to what is there. is it just a two prong connector?

HAILERS

so right in the middle of the fem 02 clip there is a brown wire that runs just past the turbo on my s4************************************************ ************************************************** **************************************************

The brown wire in the FEM-02 is the wire that goes to the circuit opening relay on the FRONT side of that FEM-02 plug and on the Emissions side of FEM-02 it goes to the fuel pump check connector (yellow two wire plug) and is also spliced to the BROWN wire that gets connected to the AFM's electrical plug (which in turn goes the fuel switch inside the afm).

So the brown wire should have a splice in it in the engine bay and one wire of that splice goes to the afm and the other to the fuel pump check connector.

Is it needed? Not the part going to the fuel pump check connector, but you do need the brown wire going to the afm's electrical plug so the fuel pump will work or stay running once the key has been returned from START to just ON and the vane in the afm has moved aft enough to *make* the fuel switch inside the afm which in turn puts a gnd on the circuit opening relay to feed the fuel pump.

If not using the stk afm then you don't need the brown wire.

bostonspgs

iTrader: (1)

sweet yes i have stock afm , thanks for the info guys