Lights flashing in sea water

I put my BlueRov2 Hard Config. in sea water for the first time, and its four lights began to flash weakly. They were turned off. When I turned them on, they flashed strongly, like loosing contact. Worried, I came back home and did another dive in the swimming pool and then, everything worked normally, as always. I saw no sign of leakage.
What could have happened?

We have done a lot of tests in swimmingpoll and sea water.
The 4 Lumen Subsea Lights in swimmingpoll works perfectly, but in sea water they do not work well.
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When the lights are OFF and some joystick command is acioned the lights flashes.
When the lights are ON and some joystick command is acioned the lights flashes strongly and go out.
Does anyone know what could be happening?

@Gleiber @marcos.anselmo We’ll discuss internally on Monday and get back to your e-mail. We aren’t quite sure right now.

Hi all,
I’ve dived only a couple of time, only in salty water. In “manual control” mode I have the control of lights level, but in “depht hold” and “stabilyse” mode lights are turned on and they blink indipendently (maybe related to rotor?). Is it possible to turn off them and to handle the lights level totally by controller?

I did have same problem when diving in salt water. One of the lights start flashing at app 1 Hz when lights was of. I could se a small amount of water inside when i held the light with lens downwards. The problem was a bad sealing at blind plug.Last light in the chain of four.

Hi @kdm, this sounds like an electrical/noise isolation problem. There may be some conductive path that should not exist, likely as a result of water ingress.

Please contact if you continue to have issues.

Thanks everyone.
After a long time with no solution, I hired a professional with experience in electronics and ROV, since the “RCV 225”. After the problem solved, everything seems to be simple.
As we suspected from the beginning of the diagnostic attempts, was grounding. We had no problem in swimming pool, not due the conductivity of the water or sommething like this but, because the swimming pool where we tested, were isolated from the ground. At sea, there were enough grounding to show the problem.
We realized that the problem did not happen with the vertical thrusters. After somme elimination tests, when the thruster # 4 was isolated, the lumens started working correctly. Voilà!
I did not open the thruster yet. May be a small water ingress.

I think it’s important to mention the great support from everyone at Blue Robotics.
I really appreciate it.


Hello all,
I just had the same problem with lights flashing!

When I took the ROV out of the water, I could clearly see that there was a water leak into the lights, excepting the last one (the one that is “further” to the battery).
The circuits were completely damaged, so in order to make a quick (temporary) fix, I bridged the connections in all the lights, on order for the last one to be able to work meanwhile at least.

I checked the connections, and they are all fine, however, the light is still not working. There’s around ~14V between GND and VIN, but there’s not voltage in LED+ and LED-

The rest of the ROV is working as usual.

Any thoughts on what could be happening or what else to check?