1997 GTX-Intermittent loss of all 12V power

[MikeEgsx]

Hello to all! I am having trouble with intermittent 12 V power loss on my 1997 GTX. It will fire up perfectly fine one day and then the next day, after simply just sitting overnight, it will be completely dead with no gages with DESS key nor with double clicking the start stop switch w/o DESS key. Then a day later it will revert back to normal starts. On the water I’ve had it run perfectly and then found it dead again after sitting beached for a period of time. And then an hour later it will start normally. I’ve been trying to troubleshoot this on and off for about two weeks now which is made more complicated when the power mysteriously returns! Two different batteries known to be good have been tried. Starting system connections and grounds have been checked and are good as are all fuses. I’ve had the ski since new and maintained it well and all connections are clean and sound as far as I can see. There is not a trace of moisture or dirt inside the front and rear boxes.

Currently the ski appears to be “dead” but I have 12V on the yellow/red wire at the start/stop button, which I’ve verified as having continuity when pressed. The purple/red wire from rear electrical box has 12V coming into MPEM and leaving MPEM to info center. Yellow/red wire leaving MPEM and running back to solenoid does not have power. Seems like an MPEM issue to me but could I be missing something? Can the MPEM fail intermittently like this?

And as an aside, it seems there is an error in my wiring diagram in that the yellow/red running between start switch and MPEM is identified as yellow/black at the MPEM end. I’m no electrical whiz (mechanical engineer by day) but I can read. Anyone else see this in their wiring diagram or have my eyes gone buggy from studying the electrical “spaghetti” too long?!?!

Any suggestions are appreciated! - Mike

 

[artr]

I would check the 2 main ground connections and wires. The large black battery cable goes to the starter and provides ground to the engine block. The connection at the starter needs to be clean and the starter needs to make a good clean contact to the engine. There are 2 black wires on the MPEM. One of them is connected directly to ground (probably the engine block). Check for corrosion at contact points. You could also move both of these main ground cables/wires around while the ski is running (or with an ohmmeter connected across them) to check for internal breaks you can not see but would cause the ski to exhibit what you reported.

 

[MikeEgsx]

Thx! Already checked the negative battery cable. Connections were clean and tight. I removed the entire cable and checked continuity while flexing, pulling and twisting the cable and it seems to be ok. I’ll go back and specifically check out the 2 grounds coming from MPEM.

 

[etemplet]

I would start by checking the plugs for the DESS near the base of the steering as it comes through the hull. Pull the pins and clean them, make sure they are making good contact. Check the wide connectors on the MPEM where the the harness plugs in. All of that has to be clean. Check for water or corrosion on the large plugs on the MPEM. You have a connectivity issue.

I chased a problem on my 1996 GTX that was similar to your. I decided t replace the rectifier and when I removed the rectifier I found the White/gray (I believe) wire smashed under the rectifier. After I fixed that wire I never had any more issues Look for the power wires and chase them down. Check the plug where it plugs into the mag, I've had issues there. Check the mag plug resistance for the yellow wires, the positive and the ground at the plug

In the rear electrical box there is a ground that needs to be connected to the battery. I've had those wires break down and corrode so you don't make proper contact. Sherlock Holmes method is the only way. Keep checking and Good Luck !!

 

[Stevie96xp]

Hello to all! I am having trouble with intermittent 12 V power loss on my 1997 GTX. It will fire up perfectly fine one day and then the next day, after simply just sitting overnight, it will be completely dead with no gages with DESS key nor with double clicking the start stop switch w/o DESS key. Then a day later it will revert back to normal starts. On the water I’ve had it run perfectly and then found it dead again after sitting beached for a period of time. And then an hour later it will start normally. I’ve been trying to troubleshoot this on and off for about two weeks now which is made more complicated when the power mysteriously returns! Two different batteries known to be good have been tried. Starting system connections and grounds have been checked and are good as are all fuses. I’ve had the ski since new and maintained it well and all connections are clean and sound as far as I can see. There is not a trace of moisture or dirt inside the front and rear boxes.

Currently the ski appears to be “dead” but I have 12V on the yellow/red wire at the start/stop button, which I’ve verified as having continuity when pressed. The purple/red wire from rear electrical box has 12V coming into MPEM and leaving MPEM to info center. Yellow/red wire leaving MPEM and running back to solenoid does not have power. Seems like an MPEM issue to me but could I be missing something? Can the MPEM fail intermittently like this?

And as an aside, it seems there is an error in my wiring diagram in that the yellow/red running between start switch and MPEM is identified as yellow/black at the MPEM end. I’m no electrical whiz (mechanical engineer by day) but I can read. Anyone else see this in their wiring diagram or have my eyes gone buggy from studying the electrical “spaghetti” too long?!?!

Any suggestions are appreciated! - Mike

Ok sounds to me a bad connection or a bad wire. Sounds like a wire will wiggle around and get connection and some turns not I would check the wires going in and out of the back black ebox and the front gray ebox. Also check the fuse in the back black ebox. It should be a 15 amp fuse could have some corrosion on it

 

[MikeEgsx]

Thanks to all for the replies. I've been out of town for a bit and not had any time to follow up on your suggestions. I'll get back to it at some point and report back.

 

[POPPS]

Sounds like you have a “current” draw somewhere?
I believe you can check this by putting a meter in line between the positive cable and the positive post on the battery? I usually put a text light in series.
Turn you can systematically pull fuses, connections to see which one closes the test light,, that is the source of your draw.