My trusted Polaris 9300 series failed after about 4-5 years of operation. Spoiler: I was getting lazy and leaving the robot for long period in the pool. Water got in the motor assembly.
I noticed the robot was getting weaker and this week it just turned on, advanced for a few feet then the two led start blinking in alternate fashion.
I took apart the control box and robot. Tested the floating line passed continuity test on all 3 pins.
Brought the motor assembly to my local Polaris dealer after two min he said motor unit is dead. $450 for the replace part.
There are no serviceable parts.
I opened the motor. 1st sign of trouble water started to leak out as I undid the motor assembly screws.
It was a real mess inside, every covered by carbon from the motor brushes, a bit of water. I cleaned everything. but found some corrosion on the control board.

All of the motors run on 24 volts. the main motor was easy to take apart and clean. The two small motors are sealed. After cleaning everything I connected all the parts turned on the control unit. Main motor starts and works for 15 seconds then control unit flashes error. As the main motor was working, I placed each of the small motors one at a time on the Pin connector made for the main motor, each of the small motors worked when connected here.
When each wheel motor is discontented the voltage reading on the pins is 27 VDC. when the motors are connected the voltage drops to 0. I'm wondering if this means the motor are damaged too much resistance or is the control board damaged.
Also I wish I would have tried this when the robot was still working out of water after power-on do the wheels turn after the main motor starts ? And how does the unit know its underwater. I did not find any water sensor.
On the control board I traced all of exposed pins in the areas with corrosion and I could not find any shorts. Does anyone know of any business which sells or repairs the control board or the small motors ?

Finally point, seeing how this unit is made I will never leave it in the pool, and I would take it apart every year to clean the motor unit. All that accumulation of carbon can't be good over time. It would have been nice if they had used brush-less motor in here.
I noticed the robot was getting weaker and this week it just turned on, advanced for a few feet then the two led start blinking in alternate fashion.
I took apart the control box and robot. Tested the floating line passed continuity test on all 3 pins.
Brought the motor assembly to my local Polaris dealer after two min he said motor unit is dead. $450 for the replace part.
There are no serviceable parts.
I opened the motor. 1st sign of trouble water started to leak out as I undid the motor assembly screws.
It was a real mess inside, every covered by carbon from the motor brushes, a bit of water. I cleaned everything. but found some corrosion on the control board.



All of the motors run on 24 volts. the main motor was easy to take apart and clean. The two small motors are sealed. After cleaning everything I connected all the parts turned on the control unit. Main motor starts and works for 15 seconds then control unit flashes error. As the main motor was working, I placed each of the small motors one at a time on the Pin connector made for the main motor, each of the small motors worked when connected here.
When each wheel motor is discontented the voltage reading on the pins is 27 VDC. when the motors are connected the voltage drops to 0. I'm wondering if this means the motor are damaged too much resistance or is the control board damaged.
Also I wish I would have tried this when the robot was still working out of water after power-on do the wheels turn after the main motor starts ? And how does the unit know its underwater. I did not find any water sensor.

On the control board I traced all of exposed pins in the areas with corrosion and I could not find any shorts. Does anyone know of any business which sells or repairs the control board or the small motors ?

Finally point, seeing how this unit is made I will never leave it in the pool, and I would take it apart every year to clean the motor unit. All that accumulation of carbon can't be good over time. It would have been nice if they had used brush-less motor in here.