nuRyders

– Hi everybody. I’m Matt Lewis with
Hagerty and in today’s DIY,I’m gonna talk about the
basics of using a multimeter. When you’re looking at multimeters,there’s a lot of different options. We’ve got very small pocket sized deals,very expensive professional tools,and then you can get in to
just the average multimeter. This one here is great because it’s gotall of the options you’re gonna needfor checking the electrical
system on your automobile. A little multimeter like this isavailable in a lot of different places. You can find them at hardware stores,you can find them at auto part stores,you can even find them at
home improvement storesor anywhere online. An item like this which is
great for the DIY home use,$20-$25 it’s gonna do
almost everything youneed from a day to day usage. Now that we have our multimeter open,you can see there’s lots of
options as to what you can testand actually, more
connections on the frontthan there are leads that come with it. We’re gonna be focusing on DC voltage,ohms or resistance, and amperage. Depending on what we’re testing,we’re gonna be plugging the leansinto these different terminals. We’ve only got one black terminal on hereso that’s obviously going
to be our ground lead. First thing we’re gonna
be working with is voltageso I’m gonna go ahead and plug it intothis one labeled voltage. For the sake of testing voltage,I’ve got a little battery
here hooked up to these leads. Since there’s actually electricityat the end of these leads,
I’ve put down some cardboard soour metal table doesn’t start conducting. With this multimeter,there are multiple options for voltage. What it does is it basically movesthe decimal point around here. We know that cars are 12 to 15 voltsdepending on the situation so our 20 voltmax setting is gonna be plenty forwhat we’re working with
on the automobile here. You can move it up to 200 which yousee just jumps this decimal point,and even to 500 which
eliminates the decimal point. While you gain head room for voltage,you lose accuracy because you can’tsee portions of a volt
at the 500 volt setting. At 20, we’re great. We know we’re not gonna exceed 20 voltsand we get plenty of accuracy withto the hundredths of a volt. I am gonna warn you that electric carsrun super high voltage,
enough to be lethal. If you have an electric or a hybrid,I would advise just taking it to a shop. Don’t mess around with the electricalsystem on it because it is dangerous. When you’re testing voltage on a car,you’re gonna remember that thisblack lead is going to be
your negative terminal. That’s gonna be the ground. We’re gonna go ahead and hook itup to our pigtail here with the black. This red one is gonna be
the positive terminal. That, we’re gonna wanna
hook up to our positive. Here we see, this little battery Ihave is reading 13. 81 volts. That’s pretty normal for a 12 volt systemto actually read higher than 12 volts. A regular car battery’s gonna bebetween 12 and 13 if it’s functioningproperly with the car off. When the car’s running, your
charging system kicks in,you might see anywhere from 14 to 15 voltsdepending on what your alternator orgenerator is currently doing. When we’re talking about voltage,what we’re actually looking at isthe electrical charge differencebetween the negative terminal of a batteryand the positive terminal
of a battery or a circuit. A good analogy for that
is like water pressure. When you’re looking at
the water in your home,how much pressure does it have?Next thing we’re gonna
talk about is amperage. You can consider amperage
like the flow rate,so how much water is actually
coming through the system. For amperage, I am gonna have
to move this terminal overfrom our voltage setting
to our amperage settingjust like this and I’m gonna have toswing our dial over to
the DC 10 amps setting. This is gonna allow us to measureamperage instead of
voltage on this circuit. When you go to measure
amperage on a circuit,you do actually have to
disconnect the circuitand put the multimeter in betweenthe power and the load
or light in this case. I hooked up the red lead to the positiveand I’m gonna hook up the black leadto our red lead here which willcomplete our circuit
and turn the light on. Pulling just over half of an amp. We’ve tested the voltage of our battery,we’ve tested the amperage of the circuitwith the light bulb on. The final setting we’re gonna talk aboutis this ohm or resistance setting. What that is is it measures how difficultit is for electricity to
pass through way circuit. When we’re looking at a little
piece of wire like this,this is just copper wire,this should be almost zero
ohms or zero resistance meaningit’s very easy for electricity
to flow through it. If we go ahead and hook
our terminals up here,once this settles we’re at . 3 ohms. This may just be a variance ofwhat the multimeter can read becausethis is a fairly inexpensive multimeter. It may be this does have a tiny
bit of resistance in it but,basically we’re looking for a verysmall number when you’re readingsomething like just a piece of wire. Right here I’ve got what
is an ignition coil,I believe it’s off of a little motorcycle,and measuring across these two points,we’re gonna see how easy it is forthe electricity to flow from side to side. We hook this up and we see
about five and a half ohms. That’s more difficult for electricityto flow than just this piece
of wire but, still fairly easy. That’s not a lot of ohms. For the sake of testing all threethings we’ve talked about today,I’ve gone ahead and made
our light bulb broken. This light doesn’t function anymore. We hook power up to it. There’s no light. First thing we’ll test is voltage. We’ve got our voltage set back up,we’ll hook up to the negative terminaland positive terminal. Electricity is getting to
this point in the light bulb. Next thing we’ll test is amperage tosee if that electricity is actuallyflowing through the light bulb. Go ahead and switch that over to amperage,move our terminal over
to the amperage terminal,and we remember we put the amperagein line with our circuit. Go ahead and hook this up. It’s reading nothing. I know that this circuit
is not completing,meaning there’s something
wrong inside the bulb. The final test we can do is our ohm test. We’ll go ahead and move this back to ohms. We’ll put our meter back on ohms. We’ll go ahead and hook this
up and it appears to be open. The meter didn’t even react. What that means is there is nothingconnecting this wire and this wireand that’s why the bulb’s not lighting up. Now we know we’re gonna
need a new bulb in herebecause the electricity can no longerflow through it causing it to light. We can replace this bulb and
just see if we can fix it. For the sake of troubleshooting,what we’re gonna do is we’re gonnaactually measure the
ohms of this light bulb. The way you do this is these
bulbs, this is an 1157 bulb. It’s super common for cars. This outside ring here
is the negative terminaland then what you have is
two positive terminals. It’s called a dual filament bulb. If you look really close you can seethere’s actually two filament sections. Those are what produce the light. We’re still on our ohm setting sowe’re gonna go ahead and
connect to the negativeand then probe this positive. It didn’t even react when I hooked it up. There could be a couple of issues. These connectors here that
hook the socket to the bulbmight be corroded or broken,this outside may no longer be groundingproperly to our negative terminal,or really where these wires go inmay be broken or kind of anywherewithin this circuit it may be broken. We grab a new bulb, we put it in. Now we can use the same ohm
test, hook up to our terminals. We’re seeing the numbers respondingwhich means electricity can
flow through this circuit now. What that means is we have a good bulband a good housing with good wiring. Now that we’ve fixed it,if we hook our battery
up, we have light again. If you find yourself with a brand newmultimeter that you want to play with,you can do it with something assimple as a double A battery. Here we’ve got a positive
terminal labeled,it says it’s gonna be 1. 5 volts. You can hook that up and play with that. I hope this multimeter DIY was helpful. If you have any comments or questions,go ahead and post them below. Make sure to subscribe to our channelso you know whenever
we put out a new videoand we’ll see you next time.

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