96 XP DC-CDI module testing help

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turbodriven

Member
I have a 96 XP with a no spark. I've tested just about everything from bow to stern.

A short run up. Everything tests good with all the Seadoo manual tests and a multimeter. Ignition coil, MPEM, Trigger coil, Stator etc etc. All within specs. I'm not getting a pulsing light when I test my white wire at the rear box though. The white wire has good continuity from inside the rear box to inside the front box so the wiring itself is good it seems. The wiring in the whole ski is very clean actually, very little corrosion throughout.

That all being said, the only component that doesn't test to spec was the DC-CDI box. All the tests were way off spec (see attached graph). So I bought tested a different one (which I thought was off a running ski), with almost the same results. So then I tested a third in some guys garage on one I was going to buy (didn't write down those figures) but the were almost exactly the same as I remember.

Did I just get my hands on three bad DC-CDI boxes? Is my luck that bad? Or am I missing something?

It would be SUPER HELPFUL is if someone had a 100% known working DC-CDI box from this year and ran these same quick multimeter tests for me. Just maybe the first three on the chart I've attached (RE/PU, YL/WH, and WH)? Or tell me from personal experience that all three of these boxes I tested ARE just bad. I just hate to spend $200-300 on another used DC-CDI box and it not be the problem.

As a side note, does anyone know WHY these things go bad? Or how they fail rather? Just heat/age?

Thanks
 

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I had a similar issue on a 96 GTX and invested in 2 additional CDIs because of the difference in resistance measurements from the manual. I recorded the readings but they are in a remote location where I keep the jetski. The issue that I had was sometimes it would crank and crank and not fire. If it did start then it would run fine until sitting for extended periods. The issue for me turned out to be an intermittent holder relay. That relay turns on power to the CDI when the ski starts and runs and shut power to the CDI when you turn the ski off so the battery does not drain. You can hear the relay click on when you put the key on the dess post. What I found by putting a voltmeter on the relay output is that it would turn on and supply 12V to the CDI when the key was installed but would drop the 12V (sometimes after long periods of sitting) immediately when the start button was pressed and the starter engaged. You can easily test for a similar issue with a voltmeter on the output of the holder relay or just temporarily short the 12V to the output of the holder relay (red/purple stripe wire) to see if you get a pulsing test light on the white wire. Also check that the 5A fuse on the holder relay assembly is good and the 2 CDI connectors are clean and making continuity between the CDI and the other locations, especial Ground to the CDI. I ended up selling the 2 additional CDIs.

I think that CDIs could fail from moisture intrusion, over voltage conditions or just an internal component failure (age).
 
Thanks for the reply. To be honest I didn't fully test the relay. But what I did do was unplug the RE/PU that goes from the relay to the CDI and when the DESS key is inserted, the wire showed 12v. So the relay was "functioning" I thought. But I know that the manual has a range of more involved tests that I didn't fully understand so I didn't do them.

That said, I do have a spare holder relay that I could just plug in to see if there is a change (assuming my spare is in working order). All the fuses are good and all the wiring/plugs seem to be in good condition though, that's the first thing I checked. Not a spot of rust on anything wiring related anywhere. It costs nothing to swap the relay out though, so maybe I'll check that now.

I've been doing a bit of research on CDI's in general. And it appears as if the main issue is that typically the solder joints crack and delam with age and it breaks the circuits inside the units. At the end of the day I might try to de-pot one of these and take a look at the circuit board. If the CDI is actually bad, I've got nothing to lose I image. I've been known to be handy with a soldering iron, lol.
 
My holder relay passed the static test from the manual but failed as described. Does the ski give the 2 beeps and light up the gauges when the key is installed? Do you know the MPEM is or was functioning? I wouldn't dig in the CDIs until you determine what is really wrong.
 
Yeah, digging into the potting on the CDI will be a last resort.

To answer the question, yes DESS key produces two quick beeps and all the ohm tests on the MPEM (per manual) were good. It cranks, gauges light up, I don't suspect there is anything wrong there.

I'll do some more testing around the holder relay. I'll swap it out first. Then I'll try connecting 12v directly (bypassing the relay). See what that does.
 
Ok, so for what it's worth, I'm pretty sure the holder relay is not the issue.

I ran through both static test and dynamic tests from the manual which both passed. I connected it on the bench and the relay clicks and works as it should. I installed the other relay I had just in case on the ski, no change. And then I connected both RE/BL and RE/PU straight together (bypassing the relay altogether and supplying the CDI with direct power), still no change. Still no spark from a grounded plug, or even a flicker off the white wire on a test light.

It can only be the CDI I think at this point. But I'm still open to ideas. I'd still love to see test results from a known good CDI to confirm.
 

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While it is not impossible to have 2 bad CDIs I have read about problems with the pickup coil in the magneto moving because the bracket that holds it loosened or rusted. I think the pickup coil would still static test for the correct resistance but would not trigger the CDI to fire if it were out of position. There is a special test box the dealers had to dynamically check that but I don't know if there is another way to test it dynamically. I would think you see a small voltage fluctuation between that trigger signal and ground with the CDI connected either by cranking the engine or rotating it by hand with the plugs removed. I have never had to test for that so maybe someone else could recommend other dynamic test methods.
Also, maybe there a another member near you with a 96 XP, GTX or GSX that could test your CDIs.

Here is an excellent video on the subject of no spark in a 96 XP:

 
I just overhauled the whole engine and had the stator cover off before reinstalling the engine a few weeks ago. I can guarantee the pickup coil isn't rusted or loose. So long as it's in the bolt holes and tight, it should be aligned proper though I think? That said, I wish there was a way to dynamically test the signal pulse without an oscilloscope (which I don't have)? Then I could rule that out all the way.
 
I can test mine this week for you but will be a few days before I can get to it. I had a similar issue with my 96 XP a few years ago. I tested everything and it turned out the MPEM just randomly failed. If I remember correctly, my CDI had some weird readings compared to the service manual but turned out to be fine.
 
I can test mine this week for you but will be a few days before I can get to it. I had a similar issue with my 96 XP a few years ago. I tested everything and it turned out the MPEM just randomly failed. If I remember correctly, my CDI had some weird readings compared to the service manual but turned out to be fine.

That would be amazing. My goal is just to know what an actual proven running ski tests at. If a proven running ski still has Ohm readings that are all over the place I'll feel less secure about the DC-CDI being the problem. And vice versa.

The only other thing I'm thinking about is that pickup coil not being close enough to the flywheel. But I'm not aware of a dynamic test to check the signal (the static test for the pickup coil passes though).
 
Here's the readings I took on 3 CDIs. They were all good.

Very interesting that a lot are not in spec but the DC-CDI is perfectly good. Throws a real wrench in the gears over here because now I can't trust anything I see. Ugh. Thank you so much for taking the time to submit these!! I think I'm going to pull my stator cover off and somehow try to confirm the pickup coil is in the right place. It's the only thing I can think of at this point. And a long shot since I just buttoned it up fresh on the rebuild and am pretty sure it's good.
 
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Just to put a nice pretty bow on this thread, I found out my problem.

When I bought this ski (in rough shape) the previous owner said he put in a new stator in while trying to chase down some type of "imaginary" electrical gremlin. In hindsight I now realize that he installed an Ebay special stator. When I had the motor apart it looked good and I static tested the stator and trigger coil and they both passed every test. But that crappy Ebay sh*t was the issue.

The problem was that my Ebay trigger coil shape didn't match the OEM one. It's too short. Therefore it wasn't reading the flywheel marks as they passed. Into the trash can you go. The funny part is, that the OEM stator he gave me was just fine. I'm not sure why he replaced it. <facepalm>
 

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Yep, the Trigger Air Gap is critical.

Something that's always checked on A/M Total Loss Ignition Systems but usually not on Stock OEM Systems.

Chinese Parts are always a gamble.
 
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