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I'm having the same problem as this person - no matter the setting, my multimeter always shows a resistance of 1. I tried touching the probes together - still 1.

Is my multimeter faulty? Or am I doing something wrong? Help!

enter image description here

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    \$\begingroup\$ This usually means "infinite", most likely because the cables or probes are defective. Or you pressed the "hold" button while the probes have been disconnected. \$\endgroup\$
    – Janka
    Oct 9, 2017 at 0:22
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    \$\begingroup\$ Can you try removing a probe and touching the other probe to the opening? (do it with both) to test if one wire is bad somehow - also on a lower resistance setting perhaps would help \$\endgroup\$ Oct 9, 2017 at 0:23
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    \$\begingroup\$ Try to measure a voltage, current or continuity. If you get a correct measurement then the leads aren't likely to be faulty and the meter has a problem. \$\endgroup\$
    – Wesley Lee
    Oct 9, 2017 at 0:45
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    \$\begingroup\$ @Janka - the hold button wasn't pressed - I played around with that button a bit and it definitely displays the "H" correctly when active. \$\endgroup\$
    – shelman
    Oct 9, 2017 at 1:24
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    \$\begingroup\$ Continuity is just shorting the leads together, but instead of showing resistance it should beep. Voltage you can measure with a battery for example. \$\endgroup\$
    – Wesley Lee
    Oct 9, 2017 at 1:33

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Is my multimeter faulty?

In your photo, we can see that the probe leads are plugged into the correct sockets on the meter, and you have selected the 200 kΩ resistance range on the dial.

As you may know, a multimeter display showing only "1" in the left digit position, usually means over-range i.e. the measured value is in excess of the maximum for the selected range. On meters with only manual range selection, like yours (or when using manual range selection on an auto-ranging meter) you could switch to a higher range, to see if the meter then displays a value within that higher range.

In your picture, you have selected the 200 kΩ range, so your meter display suggests the resistance is >200 kΩ which is obviously incorrect for the low resistance expected from shorted probe leads.

Therefore either the multimeter, or one (or both) of the probe leads is faulty.

You could try unplugging both leads from the meter, and shorting the "COM" & "VΩmA" sockets (i.e. the sockets where you currently have the probe leads), using a short length of known-good wire.

  • If you then see a low resistance on the meter, then the meter is (at least basically) OK and you can move on to test the probe leads individually, by replacing that known-good piece of wire with each probe lead, in turn.

  • If you still don't see a low resistance on the meter with a known-good length of wire shorting those two sockets, then that points towards an internal problem with the meter itself.

Note: As shown in the question that you linked, it is possible to have incompatible probe leads, if they don't fit correctly into the sockets on your new meter, and hence don't actually make electrical connection with the meter itself. Be aware of that possibility.

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  • \$\begingroup\$ When you refer to shorting the sockets - does that mean sticking one end of the wire in each? So to short it with the red probe, for instance, I would plug it as normal into the red socket of the multimeter and stick its lead in the black socket? \$\endgroup\$
    – shelman
    Oct 9, 2017 at 1:23
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    \$\begingroup\$ @shelman - "does that mean sticking one end of the wire in each?" Yes, exactly that. Personally I would start with a known piece of different wire, if you have one (or even a straightened paper clip) as that will totally eliminate use of either of the existing probe wires for that test. Only after that confirms a sensible (low) meter reading would I then move on to testing the probes individually, as you suggested next in your comment. You could use one of the existing probes first, as you suggested, if you prefer, but be aware of the possibility of poor socket connections as I mentioned. \$\endgroup\$
    – SamGibson
    Oct 9, 2017 at 1:30
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    \$\begingroup\$ I got a low resistance when using the paper clip, and a 1 when testing each probe individually. Looks like I need to replace the probes. They do have that weird sheath on them which it seems like has caused other people problems, but they came with the multimeter so I assumed they'd fit. \$\endgroup\$
    – shelman
    Oct 9, 2017 at 1:57
  • \$\begingroup\$ @shelman - Yes, sounds like the probes might have incompatible plugs for that meter. If you want to prove that: With the meter set to a resistance or continuity setting, use that straightened paper clip as an "adapter" between the suspect "plug" end of one of the existing probe cables, and the meter's socket. Of course you would need to hold it in place - e.g. gently put the pointed end of (say) the red probe into the COM socket; hold the paper clip so it connects the other end of the red probe lead and the VΩ socket. If that now gives a valid meter reading, the probe plugs are incompatible. \$\endgroup\$
    – SamGibson
    Oct 9, 2017 at 2:08
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    \$\begingroup\$ @SamGibson some probe plugs have no exposed metal, \$\endgroup\$ Oct 11, 2017 at 8:47

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