2017 seadoo RXT 300 U16A5, U16A4

[IvanNik]

Hi All, need your help.
2017 seadoo RXT 300 rebuild..
IBR goes random (up and down) + limb mode
errors: U0129, U16A5, U16A4.

Also previously got all these errors: u0129 U16A4 C2144 C0042 C0043.

New battery, new IBR, new IBR socket connection, new brake lever, new fuses, new relay.
checked main harness, especially CAN BUS - no shorts or damages..
checked CAN resistance, disconnected all modules (ski mode, depth)

Any next steps? CAN oscilloscope test?
Would you recommend to test new harness or new ECU?

no rush, enjoying the process
you may see in the video the moment when IBR gate position jumped, after that - check engine + U165A, U164A, the bucket goes down

 

[IvanNik]

voltage is jumping to 16V, even to 18V..
ordered voltage regulator

 

[IvanNik]

The issue was in Lithium X2Power (Lithium Iron Phosphate). Probably it has BMS that stops charging and as result voltage goes to 16-18V..

Put an AGM battery and that solved all issues.

 

[Greg]

Glad to hear you hunted this down. Did you retest the old IBR?

 

[IvanNik]

Glad to hear you hunted this down. Did you retest the old IBR?

Yes, IBR was ok but old, so I put new motor, sold it and kept new IBR in place.

I think this is a common issue with Lithium batteries and seadoo.