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copo69
02-01-2005, 09:38 AM
how do i know when using an ohm meter wich circuit is open to supply power and wich is closed for the ground ? thank you

myclone
02-01-2005, 04:13 PM
how do i know when using an ohm meter wich circuit is open to supply power and wich is closed for the ground ? thank you

Youre questions are a little cofusing as far as terminology but I think I know what youre asking so Ill give it a shot. What type of meter are you using? An analog meter (has a needle) or DVM (digital)?

If I understand you correctly you are asking which lead to attach to ground and which one to attach to the "hot". If so the black lead goes to a good ground and red lead goes to the "hot" or positive side. If youre using an older cheapy analog meter and the leads are the same color you will need to pay attention to what the needle does when its first connected while measuring voltages. If the needle deflects to the left then you need to reverse the leads as an analog meter can be damaged by reverse polarity. If youre using a digital meter its not a big deal since most all DVMs will read either way without hurting them at all. You will get a - (negative) symbol that shows up if the leads are reversed polarity but just ignore it or you can reverse the leads if it makes you feel better.

HTH

copo69
02-01-2005, 04:22 PM
no the wires comin from my turn signal were burnt away and from looking at a diagram the grounded side also ties into the sending unit for the fuel gauge ,. in trying to hook them back up correctly i was wondering how i could tell wich of the snubby wires was the hot wire and wich was the ground . i have a digital meter and i was wondering what readings i would get for grounded and what for open power. does that help /

KWIKND
02-01-2005, 04:46 PM
Copo,

If you are talking about the wires that come out of the bulb socket, the wire that goes to the center contact of the bulb is hot and the wire that goes to the outer cylinder (socket) is the ground. You should not need a DMM for this as the socket is not grounded if the wires are not connected.

Good Luck
Dan

Milow68
02-03-2005, 10:31 PM
Quick FYI
Don't try to use the ohm setting when the power is on!!!!! Resistance is to be read without power. Current and volts you have to have power one.
Just my.02
Brad