For more on “control testing” see Section 22 “No Start, No Spark Diagnosis” in my eBook available at www.scannerdanner.com How to perform a no start, no spar…
How to troubleshoot a no spark condition with a test light (Subaru)
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I was actually skeptical with the test light test. But then he confirmed it
with an amp draw test… Nice
col video.!!:):)!!
Is there are particular kind of test light you need to be using to do these
tests? I’ve noticed you use two different test lights in your videos.. the
clear one is this video and a red one in others. Would a logic probe or a
power probe work too?
That test would work here too. Don’t remember if it was a pull up design or
not but either way, even if it was a pull-down, it would still work with
the correct polarity on your test light.
Hi, I saw the case study you posted on the GM igniter bypass, Re: switches
etc. The tests in this case seem pretty conclusive, however could we for
instance place a intermittent voltage to the igniter at the terminals that
come from the ECU, via a test light? assuming that the circuit is a pull up
design? Thanks, Chris. P.S great instructional presentations.
Is it the exact same wiring on the igniter as in this video? If so before
calling a bad computer you have to make sure you do not have a cam or crank
sensor problem. Washing the engine bay should not have hurt the computer
that lives inside of the car. I am worried about a messed up crank or cam
signal
Now after more testing one of my input wires aren’t showing voltage at the
ignitor. I’ve got good varying voltage on one input but the other is dead.
Ive ran a continuity test between the ignitor and ecu and have good link
but no voltage. I’ve replaced the coil, ignitor, plugs, fuel filter, and
cam/crank pos sensors. Still can only get spark on 2 cyls. Do you have any
other insights? Thanks
97 Subaru IMP with 1.8 ecu/sensors and a 2.2 longblock that ran for 5+
years until i washed the motor in Feb of this year, Next day it started
running rough, then wouldn’t even start. i found your video which pointed
me towords the ignitor, which i replaced.
disconnect the ignitor trigger wire from ignitor and ecu and check for
ground? then hook up the scope to cam/crank sensors directly or thru the
harness?
Yes same set up as the video. I’ve replaced the cam/crank sensors,
wondering if I maybe I messed up the sender on the cam?
Yes but you must disconnect it from the computer and igniter first.as for
the cam and crank a voltage test is not enough you need to see the waveform
Hmm, I don’t think theres a short to ground in the wire, can I check that
by continuity of the dead wire to straight ground? Unfourtunatly I don’t
have easy access to a scope but I do have access to a good fluke multimeter
that I’ve been using. Can I just test the wires coming out of the cam/crank
sensors for rolling voltage like I did with the ignitor?
not sure. always tough to call a bad computer. so many variables. you
really need a scope at this point to verify cam and crank signals and also
that PCM to igniter control wire. You sure that wire has no opens or shorts
to ground. I know you said it had continuity but did you check it for a
short to ground
so is it coil negative that is reading low voltage or is it the ecm to
igniter signal that you are referring to
how many wires go to each coil? 2, 3 or 4?
any time, and thank you. I promise you will not be disappointed in my
ebook. I have not had 1 negative comment about its content and usefulness
Excellent video, lesson learned , thanks Mr.Danner..
Thanks again!
Paul, your diagnostic techniques are so direct, confident, and mythodical.
You’re an inspiration. Question: could a final coil confirmation test for
shorted windings be to pulse a jumper ground to either coil control
terminal and watch for a spark out the tower – this being if no scope was
available?
I know if the engine has a disributor and a ignition module there is
usually a pick up coil inside the distributor that sends the signal to
pulse the injector , and when it stops working correctly you need a scope
to test it. i would love to see a test of the pick up coil.
@MrGingaman if your using a multimeter a 2 volt average during a crank
would be normal. remember the dmm will average the on off square wave
signal. i am assuming you have no spark? take a test light to battery
positive with key on and touch the ecu to igniter control wire on and off.
it should fire the coil. let me know result
At least the coil is acessible to get at on a subaru dam aussie ef falcon
they are hidden underneath the inlet manifold major hassle just to get at
the coil pack of a australian big straight six.
lmbo that was good, “all you nay sayers” I like that. God knows we have a
lot of those.
Hi Paul, just a question you may know does snap on stop making memory card
for mt2400 vantage? if they does how can I get like version 6.0?..
@LordValguard Of course you can, and in this case with a control problem
you would have a two cylinder misfire.
No 12v feed on this design as this igniter does NO “thinking” on its own.
It is simply two different transistors. One for each coil.
Ahhh, the old Vantage, what a great tool in it’s time and still useful
today! I learned a lot of what I know with the original Vantage.
Lets say you have a shorted coil primary but don’t have an amp probe. I
have an idea for a testing procedure with a test light. Disconnect the
switched ground from the bad coil hook up a test light to battery positive
and touch the probe to the disconnected coil negative wire from the
ignitor. If while cranking the light flickers the ignitor was going into
current limit mode and you need a new coil. Would that work?
@nesgael1 Thank you so much for your kind words. It is much appreciated.
hey man great vid helped a bit .. but still have a problem , i changed a
250t with a ej20 swapped crank angle sensors, pulleys ,intake manafold ,
wiring harness . wont start no spark , the ecu sends a signal to the
igniter pack but is less than 2 is this a problem with the ecu? tested all
wires 2 times all good. would be epic if you could help cheers
I agree, the ohm test is not good for testing coils. You need to stress
them and view the pattern with a scope to truly know if the coil is good or
not. My class is 8 weeks long and our entire associate degree automotive
program is 16 months. If you want more info on our school fill out your
name and email on my website and I will forward your info to one of our
admissions representatives. Thanks!
Yes it is discontinued, I think version 8.0 is the last update for the
Mt2400. I stopped updating mine at version 6.0 I am not sure if you can
still get one through Snap-On. Try ebay?
@foxholewilly From my experience even a good coil will not produce a spark
doing that. So I have to say a scope is necessary although if the primary
is completely shorted an ohm test should show it too but this is not 100%
accurate either. Thanks for the compliment too!