1995 GTX Beeps Repeatedly

[cmatson]

Hello all, first post but this forum has been immensely helpful in getting my 1995 GTX up and running after many years of sitting!

I recently replaced all of the fuel lines, rebuilt the carbs, cleaned out the tank, and converted the system to run on premix for my own peace of mind. I didn't touch anything in the electrical box because it had spark and ran great after going through the fuel system.

My first day on the water lasted about 4 hours before the ski died randomly and wouldn't turn back on. It seemed completed dead in the water, with no beeps or lights on the gauges.

I discovered that the electronics box had water leaking inside, so I ordered a brand new aftermarket MPEC, rectifier, starter relay, and ignition coil. I wanted to replace everything just to make sure I solved the problem! After wiring it all up according to the aftermarket wiring diagram, I get two beeps when installing the key, but upon pressing the ignition button it just beeps continuously... What's weird is that if I unplug the two purple wires and the tan wire going to the gauge, I can hear the solenoid in the starter relay clicking when I press the ignition button, but it still beeps continuously.


Here is what I've done to troubleshoot it so far:
-Battery is confirmed good, tested in the other ski (also 1995 GTX) and it starts it up easily
-MPEC is also good, it runs in my other ski and fuses are fine
-Starter motor is good, if I bridge the gap on the starter relay the engine turns over
-Starter relay is good, tested it in my other ski and it works fine; also for a sanity check I put the other ski's starter relay in this one and got the same beeping problem
-removed the temperature sensor wire to see if it was an overheating fault; made no difference

I'm at a loss at this point and really really confused.. any help would be much appreciated, here is a video of the issue:

 

[mikidymac]

You either got the wrong MPEM or it is just bad out of the box like a lot of the aftermarket ones. Your ski does not have DESS so you should not be getting any beeps. On your ski the beeper is only an overheating alarm.

Get a good OEM mpem/cdi unit.

 

[cmatson]

You either got the wrong MPEM or it is just bad out of the box like a lot of the aftermarket ones. Your ski does not have DESS so you should not be getting any beeps. On your ski the beeper is only an overheating alarm.

Get a good OEM mpem/cdi unit.

I thought the MPEM was the problem, but when I connected it to my other 1995 GTX it started right up.

Where is the most reputable place to source a quality MPEM unit?

 

[SIMPLEARKANSAN]

Westside Powersports. I just ordered one w/a matching key for my 1997 GTX

 

[artr]

You said the aftermarket MPEM worked in your other GTX and you tried disconnecting the temperature sensor and that didn't change anything. If you just disconnected the temperature sensor at the sensor then I would check with an ohmmeter if the temperature sensor wire (Tan) is shorted to engine ground even when removed from the sensor. If it is then trace that wire to find out why.

 

[cmatson]

You said the aftermarket MPEM worked in your other GTX and you tried disconnecting the temperature sensor and that didn't change anything. If you just disconnected the temperature sensor at the sensor then I would check with an ohmmeter if the temperature sensor wire (Tan) is shorted to engine ground even when removed from the sensor. If it is then trace that wire to find out why.

Just checked the wire and confirmed it's not grounded even when disconnected from the sensor. Just to make sure I wasn't crazy, I intentionally grounded the temperature sensor wire and immediately the buzzer sounded one continuous long beep just as it should when it thinks the engine is overheating.

This continuous single beep is not the same beeping (on about half-second intervals) that I hear when pressing the start key. And as you said, the aftermarket MPEM works fine in the other ski where it doesn't beep at all when attaching the key or pressing the start button. Very puzzling.

 

[artr]

Since you have 2 of the same skis did you try the the good OEM MPEM in the ski that is giving you a problem? If it does not work of behaves the same (odd beeping) then there must be something that changed in the the problem ski when it got wet. Maybe there is water/corrosion in an electrical connector, a short or something miss-wired in the harnessing, water/corrosion under the magneto cover. Also if the good OEM MPEM does not work in the problem ski it would be worth checking the MPEM that got wet in your good ski if you have not already done that.
It is probably a good idea to disconnect your gauges like before while testing just to see if anything changes.

 

[Poormanracing]

Disconnect the oil light sensor and check that.not sure if it is just a dummy light or alarm also.there is only 2 ways the alarm will go off on those over heat and oil.there is nothing to shut it down tho.check the tether sometimes they don't get pushed down enough and won't start.

 

[cmatson]

Since you have 2 of the same skis did you try the the good OEM MPEM in the ski that is giving you a problem? If it does not work of behaves the same (odd beeping) then there must be something that changed in the the problem ski when it got wet. Maybe there is water/corrosion in an electrical connector, a short or something miss-wired in the harnessing, water/corrosion under the magneto cover. Also if the good OEM MPEM does not work in the problem ski it would be worth checking the MPEM that got wet in your good ski if you have not already done that.
It is probably a good idea to disconnect your gauges like before while testing just to see if anything changes.

Disconnect the oil light sensor and check that.not sure if it is just a dummy light or alarm also.there is only 2 ways the alarm will go off on those over heat and oil.there is nothing to shut it down tho.check the tether sometimes they don't get pushed down enough and won't start.

Thank you both for the suggestions, I made some progress today that revealed more problems than answers, but has led me to believe the water damage has likely caused something outside of the electric box to fail.

-The OEM MPEM from the other ski does not work in the water-damaged one. No beeping, but also zero signs of life.
-The aftermarket MPEM (which works in the other ski) is clearly giving power to the starter relay, but only with all of the gauges disconnected. The engine does not turn over, but with the gauges and beeper disconnected, I can hear the relay clicking audibly. Switching out the OEM/aftermarket relay yields the same result.
-The (supposedly) water-damaged OEM MPEM actually works in the other ski... which now has me thinking it is something unrelated to the electronics box that caused the water-damaged ski to stop running. Maybe the magneto cover that you mentioned? I am going to do some research on the correct resistances for each of the components coming into the electronics box and try to diagnose why the MPEM's aren't able to get the ski to turn over let alone run.

Are there any common failure points with the magneto or other engine connection points that could cause a ski to neither turnover nor run?

Thank you all again for all the help!

 

[Poormanracing]

Make sure ground wire to block is good maybe run a quick jumper from battery to the block any where and make sure grounds are good.not sure if it's the newer 717 that had a ground wire from the stator to the top of the mag housing those get shifted up and cause a loss of power

 

[cmatson]

Make sure ground wire to block is good maybe run a quick jumper from battery to the block any where and make sure grounds are good.not sure if it's the newer 717 that had a ground wire from the stator to the top of the mag housing those get shifted up and cause a loss of power

If I bridge the contacts on the starter relay the engine turns over, so I had assumed the ground connection was all good there. I'll still check it and also see if there is a separate ground from the stator in the next few days, thanks for the quick reply!

 

[artr]

Something to try to isolate where there problem might be would be to disconnect the wires coming from the magneto to the MPEM (usually a plug on the front of the magneto cover will let you do this). See if that lets the problem ski behave more normally when attaching the key and pressing the start button. It won't run but if it cranks the engine that would indicate something wrong in the magneto area. Also try disconnecting the Red wire from the rectifier that goes to the MPEM and try attaching the key and pressing the start key. I would try each of those disconnects separately and then together.

 

[cmatson]

It's been a while, but with newfound motivation and sunny Florida weather, she's up and running again!

Turns out the ground wire going to the magneto had cracked inside of the wire sheath. It looked good on both ends but after some multimeter testing and pulling back the insulation I found the gremlin. I spent almost $350 on new electronics just for it to be a broken connection, but you live and ya learn lol.

After replacing the entire wire (I was worried the visible corrosion would cause it to crack again) she turned over and fired up right away! Super happy that the carbs were good to go after rebuilding them all the way back in October.

Thank you to everyone for the help!