Recent content by skiasylum

Probably go with the Seadoo recommendation for the second battery.

Secondary Battery Harness Kit 295100991 - Personal watercraft | Sea-Doo - USA Not sure why but it doesn't fit your ski, dealer would know more.

Very good then, the proper sequence should be for the ECM to power down the ski 15 seconds after it notices there is no key on the dess post. Your issue is not common. The dess post switch is sticking closed, the start/stop switch is stuck open or closed, or the ECM is toasted. I am a little...

Was the battery connected to the ski while being trickled charged since last summer?

First step with electrical gremlins is to make sure your battery is good, take it out, charge it up and have it load tested.

You should be seeing "enter level" not "enter speed", "enter speed" is what you should see when setting the speed limiter mode. From your manual "To exit the selected speed control mode, press MODE button or long press SPEED CTRL button." or your speed is above 9mph when trying to enter the...

What happens when you wake up the ski with the start/stop button, put the key on the dess post (2 beeps?) and then try to start it?

Probably is a repercussion from being sank, how long was it under water and how long did it sit sit before it went to the shop? Was the shop a Seadoo Dealership?

A 3M marine epoxy with a filler, they have different fillers for different jobs. West Marine has knowledgeable associates if you have a store nearby. I have used it to repair damaged hulls on small sailboats. Stronger and waterproof which fiberglass is not. Gel coat after the epoxy. Any cracks...

A small battery BMS is designed to protect the battery it is managing, not the vehicles electrical system/charging system the battery is storing power for. By protection I am referring to a system to help prevent the battery from catching fire and burning up the vehicle its storing power for so...

Engine Charging Systems With Lithium Batteries | Fact Sheets Good article, if you scroll down it talks about the Rotax charging system and Lithium batteries

One plus feature of LiFePo batteries is their ability to accept higher charge (C) rates than lead acid batteries. So usually when an alternator or magneto charging system designed for lead acid is put in the picture even with a BMS, a DC/DC charger is used to limit that charge rate. Seadoos...

Darkness of the oil is not a great indicator of its condition.

Seadoo also started the MPEM to ECM transition in 2006 and by 2008 it was mostly completed. Electrically the 2008 is a better ski.

Speaking of current flow, the rectifier part of the regulator/rectifier uses 3 diodes to rectify AC to DC. If one of the diodes is bad and allows back flow of DC current from the battery to the DC circuits you can get all sorts of weird events. You can test the diodes with a multimeter. Its free...