Seadoo rxt 255 Dess post question

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Geert M

Member
Hi fellow members,

I am from the Netherlands so excuse my English 😅 I have 2009 rxt-x power supply issues. Completely dead….I already replaced the starter solenoid, the starter relay and brand new battery.
After a day searching for my problem I found out that it’s a ground issue. When I connect or make contact for like 1 sec, between the black and black/purple wire from the Dess post to each other then I hear the relay click and the dash lights up and al systems and engine work. The lanyard key works as wel. When I take the key of the post and return again fast system stil works. But when I wait for about 30 sec, i hear relay click again and then system is dead again. The key will not return system on. Wil it be the dess post itself? Already spent 200,- for battery and starter relay.

Hope someone can figure out what I mean and offer some good advise.

Greets from the Netherlands
 
BRP was transitioning its start circuit from the dess switch to the start/stop switch around that time to power up the ski so troubleshooting is convoluted to say the least. Since you have bl/pu wire on the dess post I'm assuming you have the 4 wire dess post so powering up your gauges should happen when you press the start/stop switch. Sounds like the ECM is trying to provide the ground thru the black wire so and the bl/pu receives power from the battery 30amp relay relay in fuse box 2. Troubleshoot that relay, then the start/stop switch and circuit, then the dess post. Good luck.
 
Thank you for your reply!

Yes I have the 4 wire Dess.
I normally put the landyard in and system (dash and fuel pump, etc) turnes on. Never needed start/stop switch for this.

I’ve tested the relay on a extern battery today and that works properly.

When I give the black / purple wire a touch whit any other grounded wire, the hole systems jumps to life.

Thanks again for your thoughts 🙌🏼
 
Would not a proper working DESS Post and key provide the proper contact between your bl/pu and bl wire to complete the circuit? Another scenario might be on/off switch is stuck closed/on if when bl / pu wire contacted to any ground powers up the system without the DESS key installed, although it is usually a bad DESS post when its the 4 wire one.
 
Would not a proper working DESS Post and key provide the proper contact between your bl/pu and bl wire to complete the circuit? Another scenario might be on/off switch is stuck closed/on if when bl / pu wire contacted to any ground powers up the system without the DESS key installed, although it is usually a bad DESS post when its the 4 wire one.
I will order a new 4 wire Dess and see what will happen. Thx for your help!
 
I will order a new 4 wire Dess and see what will happen. Thx for your help!
Well here’s a update, new Dess post arrived, installed it but now the ski is completely dead.. even jumping the 30a relay doesn’t work anymore. Then I Replaced the post back with the old post and ski comes to live when I jump the relay. Gives 2 beeps and I can start the ski. I am out of idea’s. So I replaced battery, solenoid, 30a relay, Dess post and cleared al ground connections. But still no fix. When ski runs it runs good, but shuts off whenever it wants. Can it be the Dess post came dead on arrival? Can it be ECU? This was replaced in 2019. But works perfectly when relay is jumped with ground feed.
 
There are 3 separate procedures in your service manual to check operation of your start/stop switch including including the use of BUDS to check the start/stop circuit. So you also need a properly functioning start/stop switch. You could either test it or replace it with a known good. I would also recommend the use of a OEM Dess post and start/stop switch. Your getting close to eliminating everything but the ECM might as well try the start/stop switch.
 
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His ski is the older system that only powers on when the lanyard is attached. Pressing start/stop won't wake it up like icontrol skis. 2009 was the first year for icontrol (fly by wire) but was only on a couple models. By 2011, everything had it. Easiest way to tell is by seeing what cluster it has.

It's a fairly simple system to diagnose. Just follow what happens when the key is put on and follow the circuits to the ECU.
 
His ski is the older system that only powers on when the lanyard is attached. Pressing start/stop won't wake it up like icontrol skis. 2009 was the first year for icontrol (fly by wire) but was only on a couple models. By 2011, everything had it. Easiest way to tell is by seeing what cluster it has.

It's a fairly simple system to diagnose. Just follow what happens when the key is put on and follow the circuits to the ECU.
Correct my system starts up when placing the lanyard. It’s holding the ground I think.
 

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Could this thing placed near fusebox maybe had to do something with it? When I disconnect this plug the ski will also cut of all power to the system
 
It's just a diode. It should cut everything when disconnected. You need the wiring diagram and basic circuit understanding.
 
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