Ground Resistance reading

[VisceralSound 10+ year member]

So I wanted to test out my grounds resistance with my DMM on the "Ohm" setting. I ran a very simple wire from my batteries negative, and put one lead on the wire, then put the other lead on the ground and I hear you want 0.05/3 or less but I'm getting like 22.4

What it looked like before I added 3 more self tapping screws and replaced the main screw with a newer longer one to the ring terminal to further secure it.

on the main self tapped screw IIRC I have 2 washers between the body of the car, the ring terminal, then 1 or 2 washers before the self tapped screw could this be the 22.4resistance reading. I was thinking about attempting to do my frame.

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[All_Logix 10+ year member]

22.4 WOW! Not to cause insult to injury here but is there any chance that the meter is displaying in miliohms?

 

[VisceralSound 10+ year member]

Maybe the batteries are getting low I don't know, but its just a standard DMM bought from Autozone I've used for reading my coils, AC/DC volts its worked fine and accurate then, it goes up and down from 22.4 by a little here and there but it averages about that.

 

[All_Logix 10+ year member]

Is the meter auto ranging?

 

[VisceralSound 10+ year member]

Is the meter auto ranging?

IIRC yes, all I need to do is put it on the setting and it goes through whatever (just setting it to Ohms, or ACV, DCV etc etc)

 

[All_Logix 10+ year member]

Sorry to ask again then but you never answered if the meter went into the miliohms range which would display 22.4 but would actually be .0224 ohms

 

[Volvowith18psi 10+ year member]

Def. check the meter range!

Try checking this way also; Jam 1 lead into the end of the wire, and 1 on the ground spot itself (not ring term, bolt, or w/e) In theory, this method will check everything from the washer, to ring term, wire itself.... If you really are curious if this will work, can always jam a resistor somewhere in the middle of 2 wires, observe results. Should read the same as the resistor in the line. (AFAIK)

Low / 0 reading means is a good ground, and connect away AFAIK.... I went through this myself when checking for ground spots.

 

[VisceralSound 10+ year member]

Sorry to ask again then but you never answered if the meter went into the miliohms range which would display 22.4 but would actually be .0224 ohms

Oh I guess thats why sometimes I see an M but AFAIK it was actually 22.4 but hey now that you bring that up, I'll have to test that again.

 

[goingdef 10+ year member]

make sure your not getting a false reading off your dmm.

 

[VisceralSound 10+ year member]

make sure your not getting a false reading off your dmm.

Hows that established

 

[goingdef 10+ year member]

Hows that established

read a speaker that you know is good as long as it reads close if not dead on then you will know you have a bad ground and test around in the trunk on different sheets the spot welds on some pieces just have a crappy resistance to them also they rely heavily on adhesive so some areas will be better then others.

 

[VisceralSound 10+ year member]

read a speaker that you know is good as long as it reads close if not dead on then you will know you have a bad ground and test around in the trunk on different sheets the spot welds on some pieces just have a crappy resistance to them also they rely heavily on adhesive so some areas will be better then others.

Being test a speaker coil? I know that works since when I tested my old type r a week ago both coils read 4ohms. (if thats what you meant)

 

[DaveVT 10+ year member]

Couldnt see very well from the pic......did you sand the spot to bare metal first?. If not then do it.

 

[VisceralSound 10+ year member]

Couldnt see very well from the pic......did you sand the spot to bare metal first?. If not then do it.

Yessir it is, wire brush attachment for my drill.

 

[goingdef 10+ year member]

well then the meters good, now start scratching little spots that you can stretch the ground to until you find a good one, my car had high readings as well in the trunk pull up the back seat along the bottom are a few bolts that are direct to the main part of the body tub, they are the ones that range in the 12-15mm