- Hey, what's up everybody,
Dustin here with Rocky Mountain ATC MC.
Today I'll be showing you how to test your ignition coil.
All right, so today I'll be showing you
how to test an ignition coil.
Now when it comes to troubleshooting the electrical
in your bike, if you're suspecting that you're having
a problem with the ignition there's many places to start,
but one in particular that will help you out a lot
is knowing how to test your ignition coil.
Now the method that we'll show you here today
is very general and very basic, so when it comes to working
on your bike, always be sure to reference
your service manual for that specific information.
Now when it comes to doing any sort
of electrical troubleshooting or testing
of electrical components on your bike, you're definitely
gonna want to pick up a digital multimeter.
Now you can find these at your local hardware store
and they can range anywhere from about $5
to several hundreds of dollars.
You don't need a real expensive one,
you'll just need one that can measure
in volts AC, volts DC, and ohms.
All right, now to begin your electrical testing
or troubleshooting, you'll want to locate and identify
the component that you're wanting to test,
and then you need to isolate and de-energize it,
meaning you want to disconnect it from the wire harness
and then remove it from the bike.
Now here you can see that we've got
a few different types of ignition coils.
Now they all operate under the same principles
and they can all be tested the same way.
Now there's slightly different variations from coil to coil
depending on the demands of the bike's electrical needs;
thus, we'll indicate the design of the ignition coil.
Now on this ignition coil we've got a primary side,
secondary side, and on the secondary side
we have two ignition coil leads.
On this one here we have one ignition coil lead.
Now when it comes to testing these, for instance
on this one here, we're gonna take our multimeter
and we're gonna place it into the ohms position,
and then we'll take our positive and negative leads
and we will attach them to the primary side.
Now these are not polarity sensitive,
so you can have your positive on one,
negative on the other, you can switch 'em around
and you'll still get the same reading.
Now a standard ohms resistance reading on the primary side
of an ignition coil can range anywhere from 0.2 ohms
all the way up to five.
Now again, that's quite a wide range so be sure to reference
your machine's specific service manual for that information.
So that's our primary side test.
We'll do lead to lead.
Now to test the secondary side of the coil,
because this one is a dual lead, we're going to take
our test leads here and we're going to place them
into each one of the spark plug caps.
Now as you can see we have quite a high amount
of resistance, right there we are reading 16.59k ohms.
Now the reason why we have such a high amount of ohms
is the spark plug cap.
The spark plug cap can add anywhere from 5k ohms
to 10k ohms to the resistance reading.
Now on this type of ignition coil, to measure
the primary side we're gonna place one of our leads
on the input for power and then we'll place one of our other
leads right here on the body, that's the metal part,
and this is our negative side.
This is what grounds the ignition coil.
Now here you can see that we're reading 0.4 ohms.
Now if we go to take a secondary coil reading,
we're going to take our multimeter lead,
we're gonna plug it in to the secondary side
so that it's touching the wire, and we'll take
our other lead, place it onto the primary side,
and here you can see that we're reading 2.785 kiloohms.
Now if we were to add the spark plug cap.
Now once we add the ignition coil's spark plug cap,
we take our secondary test reading.
It's going to add quite a bit of resistance.
So now we're at 12.86k ohms, which is quite a bit.
All right, now this type of ignition coil
is measured the same way as the others.
We've got our primary side.
We'll take our measurement,
place our positive and negative leads onto the posts,
and right here we're measuring about 0.4 ohms.
Now this is different, it's got a positive and negative
input on the primary side of the ignition coil
but it only has a single output on the secondary side.
Now again we test it the same exact way.
We'll plug our lead into the secondary side
and then we put our other lead on the primary side.
And right here we're measuring 1.7 to 1.9 kiloohms.
Now you can measure off either one of the primary side
inputs and you should get the same reading.
Now again, when we plug in or add the spark plug cap
it will increase the resistance
by about 5k ohms to 10k ohms.
So right there we added about another 5k ohms.
Now back to the first ignition coil that we tested.
If we were to take our secondary side
and measure to our primary side,
we're not gonna get any sort of resistance.
Now this doesn't mean that the ignition coil's bad,
it just means that it's tested in a different way.
So again, be sure to reference your service manual
for those specific procedures.
Now on this ignition coil here,
this is what I like to call a stick coil.
Now it's the same concept, it has all the same components
as these here, it's just a slightly different design.
Now on this one we have a primary side and a secondary side,
and again it's measured the exact same way.
So we'll take our multimeter leads, we'll place one
on each of the prongs at the connector,
and again we can take our measurement.
And to measure the secondary side of the ignition coil.
We'll measure it just like the others.
All right, now if you're taking a measurement
on the primary side or secondary side of your ignition coil
and your multimeter reads OL,
that means you have an open line or a break in the wire.
Now if you have that, you'll want to double-check
your connections to make sure that you're testing it
the correct way, and if you are connected to the component
that you're testing the way that the service manual states
that you need to be and you have the OL sign,
there may be something wrong with the component
that you're testing and it might need to be replaced.
All right, and that's how you test your ignition coil.
Now if you have any questions or concerns
as to what we've done here today,
feel free to leave us a comment below
and we'll be sure to get an answer back to you.
And don't forget to subscribe to our YouTube channel
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And see our website at rockymountainatvmc.com,
where we have the largest selection
of parts, apparel, and accessories
for your motorcycle, ATV, and side-by-side.
I'm Dustin with Rocky Mountain, thanks for watching,
and keep turning those wrenches.