- 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 for more product spotlights,
how-tos, and top fives. 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.
