Modis Hook up

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  • TomCs
    Junior Member
    • Nov 2011
    • 12

    Modis Hook up

    I'm new to the Modis and wonder if someone would offer me some help.

    I am working on a 1998 Sebring 2.5 V6. It has a random misfire, but no codes are being set. I would like to be able to see the firing on all 6 cylinders on the scope.

    How would I physically hook up the modis to be able to do this? I do have all the keys and modules as well as a low amp probe. Running version 11.4.

    Thanks for the help.

    Tom
  • Skip
    Super Moderator
    • Apr 2008
    • 605

    #2
    If the PCM lost the adaptive numerator it won't look for misfires. Drive the car and do some freeway speed coast downs. That's how it learns. Once it has the numerator, the "which cyl is misfiring" test will work.

    Comment

    • TomCs
      Junior Member
      • Nov 2011
      • 12

      #3
      Thank you for the reply. Would you or any one else tell me how to hook up the modis to see the firing parade on the scope? Can this be done through the OBDII or direct to some part of the ignition system?

      Thank you

      Comment

      • roadracer587
        Member
        • Mar 2012
        • 36

        #4
        I assume that you also have the SIA2000 Secondary Ignition Adapter. If you do not, you can not look at a parade pattern. If you have the SIA2000 you should have the user manual that came with it. It give a very good explanation of how to hook it up and bring the pattern to the scope. I would like to give the info to you in a post on this forum, but that would be a very long post. I hope this helps.
        No one plans to fail, they simply fail to plan!!!

        Comment

        • TomCs
          Junior Member
          • Nov 2011
          • 12

          #5
          Thank you. I guess that is why it did not make sense to me. I do not have an SIA2000.

          Comment

          • Rich Shepherd
            Snap-on D&I
            • Nov 2006
            • 553

            #6
            Originally posted by TomCs
            Thank you. I guess that is why it did not make sense to me. I do not have an SIA2000.
            If memory serves me, that is a distributor type ignition with the coil inside the distributor and it is located inconveniently between the air cleaner and engine. Look up the wiring in your information system to see how the system is laid out.
            If it is a Dist type, you have a few options for primary and secondary viewing if you don't have the SIA. For coil in cap type distributor systems in general, you would have better results if you used a single pickup on the cap instead of the SIA anyways.
            If the driver is in the PCM, you can back probe the coil driver and look at primary on the labscope. You could also look at coil current but how telling that is will depend on the kind of problem the system may have.
            For secondary, you would need the single kv lead and the RPM lead.
            To connect to secondary, you need a pickup that you can place on the cap over the path from the coil tower to the center button. You would likely have to use some tape or other method to hold the pickup in place. At this location you can pickup the firings for all cylinders. You have to be in the right spot otherwise you will detect the firings on some cylinders more strongly than others due to the relative location of secondary current paths in the cap.
            You can see the pickups that are available here:
            http://www1.snapon.com/diagnostics/us/vantagepro under scope accessories.
            the Modis uses the same accessories. There isn't a vehicle specific secondary pickup for that system but there are some that may work.
            The easiest way to look at secondary on that engine is probably going to be to use a small strip of aluminium or copper tape. maybe 1/2-3/4" x 2". The metal tape can be used as a secondary pickup. Place it over the coil current path just above the coil tower on the cap. leave a small tab folded over on one to connect a jumper wire to, then connect the jumper to the center of the single ignition lead. some of the alum or copper tape will have a coating on it so you may have to scratch the surface with your jumper lead to get a connection to the metal. You will want to connect the RPM lead to #1 if you need to ID a particular cylinder. You may need to use a lower kv scale such as 5 kv depending on the signa level.
            If you don't have the ignition lead, you could use the lab scope and connect one of your Lab scope leads to the tape. Start with a 2 or 5V scale with the Invert for the channel selected. In Lab scope, you will have to set a sweep of about 200 ms to see all the cylinders at idle while. If you have the RPM lead, you can set the trigger to Cyl, set the sweep to 5 ms, and move the RPM lead to each cyl to see each cyl. You could also stop the scope, zoom out, and then zoom into each cyl event to get a closer look.
            If you don't have a piece of metal tape handy, you could just place the lab scope probe or clip on the cap in place of the tape. You may be able to get enough signal to view if you select a lower voltage scale.
            I am not trying to indicate that any of these methods is necessarily the best way to go, just to let you know what the possibilities are. If you have a few minutes some time to experiment, you can see for yourself if any of them may be useful to you.

            Comment

            • TomCs
              Junior Member
              • Nov 2011
              • 12

              #7
              Rich,

              Thank you for the great information. I will be experimenting with the methods you outlined.

              Regards
              Tom

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