1996 GTX - 12V LOW troubleshooting

[Ckrawiec]

I THINK I've been chasing my own 12V low problem all wrong....my version of the '96 GTX has the integrated CDI in the MPEM (called a MAAP on my wiring diagram - I'm using a '97 diagram which matches my ski)....anyway, the wiring diagram shows the rectifier RED going into the MAAP and 2 Red/purple coming out of the MAAP...one R/p goes back to the Solenoid side of the battery connection (so this would keep the battery voltage up to snuff), the other R/p goes to the Infocenter (and I assume this is the signal wire that IF IT IS NOT above 12.6/7 VDC then the 12V LOW message gets activated - depending on what the 12V low threshold is of course).

So, if the MAAP is not putting out 13.5+ VDC back to the battery....then the MAAP is faulty I would therefore assume and it would not be the rectifier as the problem (related to the 12V low issue).

I am off base here? or on the proper thought track? Forum wisdom appreciated, as always.

Lastly....notice on the wiring diagram...the GREY wire (to Tach and Infocenter) traces back into the MAAP and suddenly becomes BR...but there is NO BR in the wire color code - wth? Also, notice...Yellow/red from SS button mysteriously changes to Yellow/black in the MAAP? again -wth?

 

[Ckrawiec]

No comments/responses yet?

Another question then too.... SO, these older skis will run without the Rectifier RED wire connected to the MPEM/MAAP (whatever Seadoo calls it at any given time), so is it correct to think then that IF the ski is not contributing any DC power to the MPEM (via the stator/rectifier functioning), the voltage required for the ignition coil is therefore being sucked directly OUT OF the battery (thus depleting the battery)?

Only makes sense since the voltage has to come from somewhere (on the WHITE wire to the ignition coil) and if Rectifier RED is disconnected (or not working properly) the battery is not being recharged and will then eventually discharge to a 12V low state.

I'm trying to make a determination IF my Rectifier is kaput or IF the MPEM/MAAP is not functioning properly (even though the ski does start and will run - carb problems notwithstanding). I'm troubleshooting this mentally as the ski is a couple hours away and I only see it on weekends....sitting on a cradle on dry land at the moment

 

[Ckrawiec]

Wow, not one comment or response? Bump!

 

[GGuillot]

Wow, not one comment or response? Bump!

You need to relax, people have lives and will eventually get to your post, and sometimes if it's not clear they won't even respond or it may take more time to digest.

I'll take a stab at it. Measure the voltage with the ski running on the hose at idle. Don't do it for long, or disengage the carbon seal so you don't burn it up. The voltage should be around 13.5. Now disconnect the red wire from the rectifier to the MPEM or MAAP, it should start dropping down to 12.5.

The MPEM or MAAP doesn't regulate DC voltage, the rectifier does, AC to DC. The info gauge is on a 12 v loop, to activate it must receive 12 volts from the pur (MPEM) and the red/pur (batt). You're correct, the red/pur is directly from the battery area or rear e box for the info gauge to sense low voltage and display a warning.

Also note, the red/pur is always hot going to the info gauge.

 

[POPPS]

The stator delivers its AC v to the reg., which converts it to DC. I am not sure if you ruled out the stator not working. In the racing scene, the top 2 stroke classes allow TOTAL LOSS ignition, they do not have a charging stator,(very light aluminum flywheel instead for acceleration), they charge their batteries between motos and over night, to last up to at least a 12 lap race. Of course they do not have GUAGES, vts, etc to draw voltage from a slowly draining battery.

 

[Ckrawiec]

Thanks for the replies.....sorry if I seemed impatient but I noticed there were many READS and no responses, so I was concerned that I was not explaining my situation clearly.

GGuillot: The running ski voltage at the battery is the "concerning part"...SOMETIMES its a nice smooth 13.5 + volts., while other times it bouncing all over the place (ski was running on water at the time tied to the dock at idle and revving). POPPS: I ohmmed out the stator wires at 0.6 volts between all legs so that sorta ruled out the stator as not capable of working (but I did not check for any AC voltage on the lines with the ski running, at that time, this was a while ago and I didn't know then what I've learned since then)....so I'll be checking again this weekend...although the ski is now on a cradle on dry land in a non-running state (playing with battery and carbs currently)...but would also like to narrow down any electric issues related to the charging system - if I can.
I was just asking for confirmation that my thought process was sound since the long weekend is coming and if I could possibly get the ski wet again that would be a bonus...although IF there was strong consensus that the MAAP/MPEM was obviously bad, then I'd have to get one from Nick/Jess.

QUESTION: Where does the "logic" reside for the ski to report a 12V low issue? In the MPEM or the guage itself? Does anyone know what the 12V low threshold voltage is? (I've always started my investigations off with a fully charged battery (at least 12.7 volts fresh, checked and load tested)...BUT the ski was still reporting a 12V low??? on the guage....this little problem has been a thorn in my side for awhile now (but I bought the ski in this state so I own it...NO RAGrets)

 

[GGuillot]

Where does the "logic" reside for the ski to report a 12V low issue? In the MPEM or the guage itself?

It's read and triggered at the info gauge.

Does anyone know what the 12V low threshold voltage is?

My observation has been it's somewhere just below 12.4 volts.