2007 RXT Charging system not working

[AbRx7]

Just purchased a 2007 SeaDoo RXT with 78 hours on it. I will try to make this a detailed as I can so sorry for making this a long post. Started it up in the driveway and was getting a LOW 12V error. Figured it was the battery so I went out and picked one up. Threw it in thinking everything was good and went to the lake. Fired it up and its still telling me that. I was also throwing a knock sensor code as soon as i got on the throttle. I figured that was in relation to the Low 12V because i wasn't hearing any pinging. She was running fantastic. Put 3 hours on it since and now the battery is down to 10.5 V. Now i know the charging system isn't working. I know the rectifiers are pretty touchy so without even testing it (ya ya) I ordered a replacement and put that in. Welp... that didn't work. I checked all of the fuses at the MPEM. On my machine there are only 2 (30A Battery, 30A Charging). They are all good. Next in line was to check the stator. I ran all 3 test and this is what I came up with. When I ohm out 1-2, 1-3, 2-3 I get .4 ohms on each winding. That passes. When I run the machine and check AC at the stator on all 3 winding's I get 24 VAC on all. That passes. When I ohm out each winding to ground I get like 45 ohms. Am I doing that correct? Seems weird that its the same on all of them. I am also pretty sure I am supposed to get 0. I checked continuity from the stator to ground and i get nothing so I know there isn't a short. At least I think...

I also tested something else. Those tests I ran right at the stator plug. I also checked back where it plugs into the rectifier. I was getting a total different set of numbers. I was thinking well maybe there is something wrong with the harness so I started checking it over, moving it around. Ran the test again and i was getting the same results as i was when I was testing at the stator. At that point i was like well maybe its a wire harness problem. Being that the numbers were good I went to try and start it to see what it was. Now when i put the key in, the relay at the MPEM goes nuts!.

So what do you think? Do I have a bad stator and a bad harness or just a bad harness? Is there any common issues with this machine that i should go to first?

Thanks
Justin

 

[Coastiejoe]

If your battery is not near 12 volts it is common for relays and the starter solenoid to kind of go nuts. Charge the battery back up and re-do the tests

Also, you didn't mention the voltage regulator. Not sure if the test method for it, but it could be the issue.

 

[AbRx7]

Well the rectifier is also the voltage regulator. Same thing different name. I bought a new one and put that in and the problem was still happening.

Good to know about the battery. I will charge that up and go from there.

not sure what is bad at this point...

 

[BMANN06]

Your stator seems healthy based on your tests, I get 0.1 ohms on mine 1-2, 2-3, 3-1 your in the ballpark, so be thankful for that (bit of a pain to change).

I would perform a continuity check on the wire harness, specifically the 3 yellow wires from where it unplugs at the MAG cover to the input of the regulator/rectifier. Was the regulator/rectifier purchased new or used? Any corrosion on those 30A fuses? I have seen this problem where the three yellow wires get burnt and cause this problem, most of the time they show signs of heat around the connectors (mag cover to wire harness) or even at the rectifier.

 

[AbRx7]

Well that's a relief on the stator. Wasn't looking forward to pulling the motor to replace it.

The fuses looked brand new. No corrosion or anything. I checked for continuity in the fuses and they all passed. I know some fuses look good yet they are bad. The one thing I didn't do was check continuity across the yellow wires. I will do that tonight

The regulator I got was brand new. Granted it was an aftermarket one but that shouldn't matter i wouldn't think. This is what I bought: http://www.ebay.com/itm/251278406193?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

the plugs on both ends of the yellow wires look good. Again not burnt or corroded. What are the chances of a busted wire

 

[KK40384]

Stay away from eBay parts when it comes to the starting and charging system. They usually tend to be more of a headache because you're thinking its new so it must work and you test everything else under the sun. If the yellow wires pass the continuity test is look long and hard at that aftermarket regulator.

 

[BMANN06]

What are you seeing in DC volts across the battery terminals when engine running? If you see 10V DC give or take, and with the tests you've done so far this could indicate that you have a broken wire, which could indicate your only getting 2 of the 3 AC phases to the regulator/rectifier. Put the meter in continuity mode (aka beep mode) and probe those three yellow wires from the connector that goes to stator and other end at input to regulator/rectifier (hopefully your multimeter leads are long enough) other wise you'll have to either make up some extensions or disconnect some of the harness to get the leads to reach.

Good luck and post back the results of the continuity test.

 

[AbRx7]

Thank you very much. My buddy has an 04 RXP. can I borrow his reg and see if that resolves the issue?

 

[BMANN06]

Thank you very much. My buddy has an 04 RXP. can I borrow his reg and see if that resolves the issue?

yup! known good parts are always handy when troubleshooting this things.

 

[AbRx7]

What are you seeing in DC volts across the battery terminals when engine running? If you see 10V DC give or take, and with the tests you've done so far this could indicate that you have a broken wire, which could indicate your only getting 2 of the 3 AC phases to the regulator/rectifier. Put the meter in continuity mode (aka beep mode) and probe those three yellow wires from the connector that goes to stator and other end at input to regulator/rectifier (hopefully your multimeter leads are long enough) other wise you'll have to either make up some extensions or disconnect some of the harness to get the leads to reach.

Good luck and post back the results of the continuity test.

Battery shows 12.1 volts when the machine is off. 11.9 when its running.

I have a really good fluke meter so I'll check continuity tonight. Cant believe i forgot to run that test lastnight.

 

[AbRx7]

Bad starter cable. There are 2 16 gauge wires molded In to it that feed the mpem. It couldn't be seen by those were both bad. It got to the point where I couldn't even start the machine. Once a load was put on the ski the voltage would drop. I bypassed those wires and made up some new ones until I order the new cable. Starts up great and shows 14 volts charging. Thanks for all of your help

 

[BMANN06]

Nice work!