Testing Amperage on a Flashlight

I’ve read a bunch and watched a few videos and I still cant test amperage with the multi meter! (yes the meters set up correctly). All my flashlights have rear clicky switches. Could that be the issue?


Are you trying to measure the amperage at thetail cap?

For the tail cap you want the positive lead on the body of the flashlight where there is no anodising. This is normally around the rim of the tube at the back if you unscrew the tail cap.

The negative lead goes to the negative on the back of the battery.

To change modes break and reastablish contact with one of the leads.

Make sure that the positive lead is plugged in to the 10 amp hole on the multimeter.

Just make sure that nothing you plan on testing has an amp draw of more than 10 amps (multimeter dependant) or you might blow your multimeter.

Have a look at the image in the link for clarity on what I mean.


maybe this helps:


I’ve done everything you’ve mentioned and I got nadda…

I don’t have a clamp meter!

Maybe you could try to explain a bit more as "can't test" doesn't tell much

  • no light ?
  • no reading on the ampmeter ?
  • reading doesn't feel accurate ?
  • ...

The light doesn’t turn on and no reading. Just the number 1 pops up.

Can i test the amperage at the head somehow??

You can but that would require unsloldering one of the leads going to the LED and connect the multi meter in series between the driver and the LED.

Your problem could be that the fuse on the multimeter is blown, or maybe the batteries in the multimeter could be low.

Head : usualy way more difficult to do as you need wires for the 2 poles instead of 1

If the light doesn't turn on then the first step is to use a single wire in place of the ampmeter and see if it turns on :If not then you are not touching the right spots

If the light turns on with the wire then you have to verify that your ampmeter functions correctly, maybe it is not set up properly or the fuse is dead

"1" on the display (not sure i understand well) usually means that it is overloaded

What meter is it?

Reads like you’re in the wrong mode. Does it say 0 when not connected?
Make sure your mm can handle the current first! Some only do mA.

Same thing happens on some of my meters (just “1” means far out of range).
My DMM has one terminal for the minus/black plug-probe, and several terminals for plus/red plug-probes.
One of these terminals is especially meant for the 10Amp range. Is your red probe plugged into that red one?

Do follow up on the suggestion of first trying with one wire if there is nothing wrong with the light itself.

Yes the red wire is plugged into the 10A terminal and yes the batteries are good. I will check if the meter can read past 10 amps when I get home.

Which DMM do you have?

What position is the dial in? A picture of your test setup might be helpful.

Etek 10709

Just covering all bases here.

The red lead should be plugged into the socket on the left. CHECKED

The black lead should be plugged in the centre where it says COM.

The setting should be on the 10 in the yellow to the left of the F at about 7 o clock.

The hold button at the right hand side at the top should be in he UN pressed position.

The button on the left hand side up top should also be in the UN pressed position.

Still worth testing with a piece of wire only. That would ensure that there is indeed an electrical path where you are making the connection and would narrow down where the problem may be.

My settings are as you described. The single wire trick lit up the flashlight so I DO have an electric connection.

I see that the 10 amp terminal on the etek 10709 is UN fused so we can rule out a blown fuse.

Which lighs are you trying to test. (Single or multi emitter, type of emitter, what driver)

Only thing left I can think of is that the flashlight draws too much current for the multimeter to give you a reading.

If it is a high current flashlight, then maybe test the meter by measuring the draw on something you know has a current draw of less than 10 amps. Something in the 1 to 5 amp range would be perfect.

The lamp doesn't light during the test so there is no current.

If the setup is ok then it looks like the 10A doesn't work and as there is no fuse for 10A on this multimeter it might be broken (the measure shunt seem to be weak as the user manual recommands to use it only 10 second max for current >5A).

The only way to know is to test it with something else