1999 Seadoo GTX Limited No Spark

[racerx3110]

If the 12v passes through as described, then I would say so.
Remember that continuity will tell you if the wire is broken, but not if there is resistance dropping the voltage, so don't substitute one test for the other.

 

[racerx3110]

I believe you have you already verified that the MPEM is getting 12v from the battery?
Keep us posted with your results

 

[dmontero]

Alright so I have so updates and the process of elimination continues....

- I checked both white wires and they passed 12v through when directly connected to the battery
- MPEM is getting 12v from the battery. I checked this at the pin on the mpem harness
- I finally bought a new MPEM. No luck. No spark. Still not getting 12v at the end of the white wires

What is weird is that I will get varying voltage readings at the white wires throughout the 2-3 hours of my troubleshooting. Sometimes it will be around 1.8-2.2 volts. Then it started staying between 3.7 and 4.25. It changes in a way that makes me think there could be a grounding issue? I chased all grounding and it checked out continuity/voltage wise but I am not super technical when it comes to grounding and how it could translate into varying voltage readings.

Another thought I had - is there another ansularly electrical feature that inputs into the MPEM and can some how be malfunctioning and confusing the MPEM? Thermo sensor switch? Rave valve?

 

[racerx3110]

Interesting, I'm trying to think what else it might be. I just searched the service manual this is all I found, not particularly helpful here: Click on it to read it. Tomorrow I'll do some checking on mine and see if I can provide more info. I have a 1999 GTX limited as well.

 

[dmontero]

Ignition module - can’t say I know what that is.

Do you have a 2nd ground on your battery negative on your gtx Ltd?

Think there is any potential truth to my ground suspicions?

I’d also be interested to know if you get 12v at your coils on the end of your white wires… just bc I haven’t really tested anything downstream of those

 

[racerx3110]

1) 2 black grounds. One from the box electrical plug, the other from the solenoid electrical plug.
2)With both white wires disconnected, no key on post= 1.313v
3) key on post and no cranking =28.23v and counts down (or drains down), reaching 1.7v
4) while cranking = voltage bounces likely due to white wires being flipped on/off with power by the mpem.

Service manual said 12v should be found but that's not what mine is showing, mine starts and runs perfectly.

 

[dmontero]

Ahh I’m confused! I definitely don’t have the 2nd ground wire on the battery though? Could you send a pic of where that grounds and test your v without that one connected?

I will add the ground when I’m back up there this weekend but I’m afraid it’s not the issue

 

[racerx3110]

Both grounded together under coil bolt. One wire to the solenoid plug, the other to the plug in the wall of the elect box. No negative wire running directly to the battery from inside this box.

 

[racerx3110]

In other words. Black wire from harness goes into the box (through the harness plug), runs to the coil bolt (grounding for coils), then a 2nd black wire runs from that same coil bolt over to the starter solenoid plug (providing it a ground).

 

[dmontero]

I have the same grounding routing in my back box. Idk what this could be!

 

[dmontero]

I’m thinking my 1.9v-4.25v that I am reading all the time is comparable to your 1.3v before the key goes in.

Could I have something wrong with my key post (think this is dess post right?) where mpem recognizes key in but gets tripped up on some other communication

 

[racerx3110]

If get #4:
4) while cranking = voltage bounces likely due to white wires being flipped on/off with power by the mpem.

Then manual test fire a coil. It can ohm correctly but be bad, I've had that happen last summer on a 99 XP. Even the manual says it could be bad. It's worth test or swap with a good one. (I actually tested with a dirtbike coil as the run the same CDI type ignition.)

 

[dmontero]

I see your point for sure and think it’s absolutely worth trying.

I’m struggling to understand how the coil “back feeds” in that scenario (if a bad coil solves this). I’m testing the volts with the coil connector off, up stream of coil. I know I don’t understand electrical very well, but wouldn’t we still see volts? Or does the coil do the work by pulling the volts? Ha now I’m confusing myself

 

[racerx3110]

In general Volts are "pressure" and Amps are "volume". Kind of Like a water hose has pressure, and the diameter of the hose is volume.
In general volts are pushed upon a component, thus too many volts can burn out component. Amps are the available volume for a components request. You can have higher amps and not hurt a component (it only gets what it asks for), but voltage can quicky cause damage because its forced/pressured upon the component.

To relate this to your question, the coil won't request volts as volts are pushed along the wire to the device (coil). The same voltage you get at the coil-end of the white wire should be the same that is entering the white wire from the mpem plug in.

I question the coil(s) because if I'm following you correctly, your engine cranks over, and your white wires at the coils are getting similar reads as mine, but yours is not being translated into spark at the coils.

 

[dmontero]

I do not get the 28v you get when your keys in. Mines steady and varies by the day (which is weird). Minimum voltage in the high 1’s and max voltage in the low 4’s. Not sniffing 28 let alone 12

 

[dmontero]

got some new info to report. Bought a new MPEM from the guys at Westside power sports.

Popped that thing in and no change in the voltage at the coils and obviously no spark. I started chatting with those guys and he asked me if I ever rebuilt the engine. I said no. But the guy before me did and he hadn't gotten it running since.

Westside told me that a common issue he has seen is that people will install a 98 mag cup in the 99. It only have (2) metal protrusions in line of (4). Sure as shit I opened the mag up and it was a 98 cup.

I have a puller and a new cup/flywheel on the way. We will see what happens this weekend....

Let me know if this sequence of events sparks any other things to note, thanks!

Here are some pics - damn clean

 

[racerx3110]

Yep..looks like yours not a 99.
I had the same issue with a broken ski i bought. After resolving other electrical issues due to loose pins in the electrical harnesses at the mpem. I was able to get it to crank over and spark but it kept back firing, which is what clued me into the the ignition timing.
I found it had the 98 mag wheel on a 99 ski. The 98 uses 1 coil(w/two plug wires) & 1 white coil wire, where as the 99 uses two, and as you mentioned a different mag wheel and also a different mpem. Stator and pickup are the same, or aleast worked without issue.

 

[shvinas]

So that means spark should be even with that older magnet.
Hello btw. I facing no spark issue the same.
Bought jetski with engine out and fully rusted. So rebuilded.
I getting 30V on white wires disconnected but they drop to 0V

 

[shvinas]

I read that trigger should be 3.5V? During cranking or when? I'm getting 0.04V when connector installed and 1.15V with connector removed, to trigger

 

[racerx3110]

DMontero, I have a clarification question, Back on post #15 you stated
"I am pulling a constant 2.2V in line with the white wires. This is when I put a 6-pin harness in and capture the voltage BEFORE the e-box and I put my other test probe on ground.

" When I try and take a V reading with the white wire plugged in (I sneak the test probe onto the remaining metal at the trigger) I get 0V. This seems weird."

You said above that you were getting voltage to the white coil wires at the end of the harness where it plugs into the rear electrical (coil box) box? Did I read that right?

Did you also say that you got 0 volts at the coil connection from the white wires?

 

[racerx3110]

So that means spark should be even with that older magnet.
Hello btw. I facing no spark issue the same.
Bought jetski with engine out and fully rusted. So rebuilded.
I getting 30V on white wires disconnected but they drop to 0V

How does yours compare with post #31?
Correct with reguards to the older magnet, but the timing will be off giving backfires.

 

[shvinas]

1) 2 black grounds. One from the box electrical plug, the other from the solenoid electrical plug.
2)With both white wires disconnected, no key on post= 1.313v
3) key on post and no cranking =28.23v and counts down (or drains down), reaching 1.7v
4) while cranking = voltage bounces likely due to while wires being flipped on/off with power by the mpem.

Service manual said 12v should be found but that's not what mine is showing, mine starts and runs perfectly.

1. Good ground confirmed
2. With no key, one white wire ir 0.2V stable other white wire was discharging and went to 0.01V. ( i think should be 0V. Otherwise is not needed battery drain)
3. With key on both wires to 31V and drop to same readings above.
4. While cranking first wire went to 0.23v from 0.2 and second not reacting at all. 0.01V

What I found more, that when both whites connectęd, have 0.01V and start cranking raise to 0.2V, both. When disconnected trigger plug, no change. So trigger sensing something

 

[shvinas]

Found spark

 

[dmontero]

DMontero, I have a clarification question, Back on post #15 you stated
"I am pulling a constant 2.2V in line with the white wires. This is when I put a 6-pin harness in and capture the voltage BEFORE the e-box and I put my other test probe on ground.

" When I try and take a V reading with the white wire plugged in (I sneak the test probe onto the remaining metal at the trigger) I get 0V. This seems weird."

You said above that you were getting voltage to the white coil wires at the end of the harness where it plugs into the rear electrical (coil box) box? Did I read that right?

Did you also say that you got 0 volts at the coil connection from the white wires?

Nice catch but I realized my probing wasn’t great. Instead of just been pulling the white white connectors off and sticking the probe into the connector directly. I get the same v as I do upstream of the rear e-box 6pin. At this point I’ve been more focused on getting the right voltage at the white wire and haven’t spent much time downstream at the coils/plugs/caps. Although I do visual spark test every time I change something to be safe

 

[dmontero]

How does yours compare with post #31?
Correct with reguards to the older magnet, but the timing will be off giving backfires.

Yea I would think I would still get a spark with the wrong mag cup too… just not timed/frequency correct