MIGHTYMOUSE

iTrader: (59)

apparently i skipped this class. i have been told i may have one and have not really found a crystal expanation of what is happening or how to fix one / how a ground should run through a car past common sense

please inform.


my electrical system is unmodified exept for a relocated battery.

scifone

the best way i have heard of is to ground everything in the same spots. muliple grounds are what is said to cause ground looping. at least that solved my probs with my stereo.

MIGHTYMOUSE

iTrader: (59)

looking in a stock f body engine bay there are grounds all over the place, you say connect these all in one spot or do you mean that they are all connected to the chassis, that is considered 'the same place'?

scifone

no, one place meaning exactly the same spot on the chassis. i have never had problems with ground looping on a car without some stereo equipment. is there anything at all that isnt stock on the electrical system. also did you notice it after changing something?

scifone

ok im sorry i completly missed the rest of the question. a ground loop sounds like a humming noise. it will increase with the rpm's and is incredibly annoying. all of my experience is through car stereo's. a ground shouldnt run through the car. if something in the rear needs to be grounded then ground it in the rear. just try and avoid grounding in multiple spots if possible. make sure the ground wire isnt longer than 18". i see that you have a rear mounted battery. where is it grounded at and how long is the negative cable? also on turbo mustangs web site you list some audio equipment. again that amp should be grounded with the rear mounted battery.

MIGHTYMOUSE

iTrader: (59)

i have an aftermarket engine control system that gets grounds too.

the ground comes out of the battery and goes to the frame. there is one power wire that doesnt go to the frame but goes to the battery. and there is one ground wire that goes to the battery that goes to the body, not the frame.

up at the front of the car the block is grounded to the frame and then the normal stuff you see under the hood that is also grounded to the frame in lots of little different spots.

i'm not trying to get rid of speaker noise but since you mentioned it my amp is grounded directly to the battery

jimmyblue

iTrader: (11)

"Ground loop" means, you have different pieces of equipment
each with a "ground", but they are not the same point in an
electrical sense; you can have DC offset, you can pick up
EMI from power line (in a 60Hz environment, making hum),
if the signal ground is the same as your power return you
can feed back switching / load transients and like that across
the resistance / inductance separating the points.

A "star ground", everybody to the same post, is ideal. But
that is more copper, copper is weight and money, and the
chassis sheet metal is "good enough" for the average buyer
and the factory stereo.

scifone

well since there isnt any "noise" then you dont have a problem with ground loops. you might try and ground to the frame instead of the body. it would probably be a better ground. using the negative cable on the battery to ground is very good. you dont have any problems there. the power wire from the battery doesnt cause any looping so you dont need to worry about that. but if there isnt any noise then i wouldnt worry about it. remember "dont fix it if it aint broke"