240sx electrical issue

[Drifter S]

ok so let me give u all my info so i can give u the question

car is a 1993 nissan 240sx se hatchbackengine is a stock twin cam ka that someone swapped in the exhaust cam on the intake side.pretty much everything is stock under the hood other than a clutch and evidently a new timing chain as there is no noise.haha.

anyway.. the issue is as follows.. when i turn the key off and remove it the oil and battery lights come on on the dash and stay on till the car is started.. the clock also does. its like the car thinks its still on and doesnt see sufficient oil pressure or voltage as there isnt any.

now under the hood u can hear a humming buzzing noise.. it comes from the 75amp alternator fuse remove it and the humming stops and and the lights on the dash go out.

so as of the past 2 days its done it i remove the fuse when i turn the car off and install it when i start it up again. but id rather fix the issue the right way.. anyone know what it could be?

i was pointed at the ignition switch but i unhooked the wiring for it and the problem persists. im thinking there is a loose ground somewhere but which one could it be.. visually they all look right. the only noticable thing i see is it lookes like there is a ground on the alternator near the engine block side. it seems as though someone frayed it either pulled it out of the terminal and reconnected it or something.. i tried taking a peice of wire and touching to to the frayed wire and the neg battery post but it did nothing..

i will prolly drop the alternator tommorrow and reconnect that cleanly but is that even gonna be my issue? anyone seen this before? also strangely enough the radio will not power up unless the antanae is plugged in.. that shows that the radio ground wire is faulty its pulling its ground from the antannae which isnt good for the head unit if i recall.

basically any info would help.. which ground is it that pertains to this and or how can i fix it.

thanx in advance for any info u can give me guys.

[Drifter S]

anyone?

[Drifter S]

ok update.. the alernator wire was not the issue its fixed now.. i also discovered the rattling i heard wasnt the alternator use its actually the relay beside it trying to click..WTF? someone help me fix this ish.. its driving me nuts..

[vancouverbc]

which relay is rattling? when does the relay click? I dont know why fuses would make a noise. check the grounds of the car ie between battery and engine and between engine and firewall. look up ground in tutorial link in signatue

this is wiring diagram showing alternator cct

http://img264.imageshack.us/my...3.jpg

[Drifter S]

ok like i said when u take the key out of the ignition the relay beside the 75amp alternator fuse is humming or clicking on and off.. not sure whats going on inside it but u can here it humming and feel it. i originally thought it was the fuse beside it vibrating which was weird..lol.

all i can see on my car as far as grounds is the one on the intake mani that goes to the battery tray which runs to negative post on the battery. i dont see any other grounds on the engine.. bought this car off someone else and im sure that it was built..i.e. an engine from this, interior from that, sort of thing. so i could be missing a ground..

but my question is it wasnt doing it when i bought it but after a couple hours drifting at the practice day it started it and i havent gotten it to stop yet. removing the fuse or relay for a second will stop the noise and stop it from trying to work.. it will also make the dash lights go out.. but its kinda annoying popping the hood everytime i park the car..

im gonna try to redo the ground on the negative terminal to chassis to intake and see if it helps or cures it.. it looks to be in good shape with no corosion but it never hurts to redo it and double check.

[vancouverbc]

zer...2.JPG

you mean the relay directly across from 75amp fuse? my car doesnt use that relay. not sure what it does. the two green relays are the fuel pump relay and fuel injector relay.

[Drifter S]

yeah that was the one.. reguardless.. i found the problem and its gotta be the dumbest one ever.. the passenger retractable seatbelt was binded.. its been trying to move forward since saturday.. picked up a co worker today and had to unclip it frm the buckle and it finally was able to move.. no issues since...basically the power was staying on till the seatbelt was able to move.. and since it couldnt it would never go off..lol.

WTF? thank u nissan..lol.

[vancouverbc]

thats interesting. thanks for reporting back. i dont have power seatbelts so i guess that is why i dont have that relay. ill have to check the wiring diagram to see what that relay does.

[Vegascorbin]

Actualy this makes sense. If you stop the car and turn off the engine before your passenger can get out you need a way to move the Belt out of the way.

I would purchase your co-worker a beverage of their choice because if they did not need a ride you proably would have spent months chaseing this:)

I will have to remember this one.

[Drifter S]

yeah well updating again..lol.. saturday at rd1 of the drift series it started again.. seat belt didnt fix it this time and i dont think it ever did.. though it made sense at the time.. monday night i began the hung for a loose or frayed wire and boy did i find it..lol.. on the driver fender well where the harness runs.. i peeled back 14 of the wires there so i spend the time after work to cut back and reconnect the harness. i did notice when i get a lot of angle at the drift events i was rubbing on the inner pinch weld and the fender.. but i am also rubbing on the top of the wheel well where the wiring is. so my solution is actually to fix the wiring which i did and step down from 16s to 15s with smaller tires up front.

sorry to mislead anyone just wanted to state the truth that i actually found.. the chewed wiring was at fault here.