RTK unit fell in water

Hello,

I have an RTK unit that fell in water. Left it in a desiccant chamber for a week and then attempted to charge. Charging light responded to the cord but the unit will not turn on. Is there anything I can do to try to repair this? Likely not but thought I would reach out. Is there any warranty I can pursue?

If the unit fell into dirty or hard water, then it needs to be very thoroughly rinsed in distilled water to remove the contaminants, then very thoroughly dried before powering up.

However, you may have inflicted additional damage by powering the unit without following those steps.

I doubt that instances like these are covered by a warranty, unless the unit is advertised as waterproof to a certain depth.

if you drop electronics in water rince the water it out right away with IPA rubbing alcohol. it will remove the water and dry faster. you’ve waited a while so something it probably corroded, time to buy a new board

Oh no! Sorry to hear it. Which RTK Unit? The RTK Torch is fully waterproof (assuming the USB cover is closed) to a meter for 30 minutes. It’s a tank. The other RTK units are a lot less waterproof and will need to be repaired.

Warranty - Generally no, we don’t cover exposure to water, but I’m happy to take a look to see if it’s repairable. Start an RMA here.

Generally speaking, the LiPo should be replaced if there’s any chance it’s been exposed to water. I personally would unplug it from the main board and find a local recycler of LiPos.

If there is little to no visible corrosion on the subassemblies, they can be cleaned in deionized water; we use either a dishwasher based DI system, or a ultrasonic bath with heated DI, followed by a nice long bake at 165F for >24 hours. I’m unsure of the efficacy of using distilled water. We generally avoid IPA as it tends to liquify and mobilize any impurities. Once the boards are cleaned and inspected under a microscope, we go through an electrical test procedure to verify operation of all the boards.

If you’re feeling DIY, you can do this. Deionized water is a magical thing. There is nothing special about our equipment, it’s just bigger/fancier for bigger throughput. If something is really broken, we offer replacement parts for the RTK Facet series.

All that said, if you need us to do it, we’re happy to do so, just let us know.

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warm them up in a vacuum oven

I’m having trouble removing the LiPo. Is there any trick to unplugging or do I just need to pull harder? Thank you for the help!

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Docs here. But I usually use wire cutters, to gently grip the flanges:

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Thanks for all the help, I’ve got the battery out, next is DI bath. We have a sonicator that should work well. Would I put all pcb’s in there, should I also wash the large plate? Also, is there any documentation for the electrical test procedure? Thanks again.

Matthew

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Nice! I don’t see any residue on the RF shielding on the antenna or inside the housing. Looks clean.

The mainboard and USB connector boards are conformally coated so they should be clean. Do you see any corrosion or badness on those boards?

The display board cannot be conformally coated because of the display connector, so it may be the broken piece of the puzzle. With the battery left unattached, what do you see when you plug in USB and try to power the unit on? Hold the internal power button - you should see the internal status LED turn on. Do you see any COM ports appear? If yes, then I suspect your display needs to be replaced. Or you can DI clean the display, bake the display at 165F for 24 hours, and see if that alleviates the issue. We also sell replacement displays if you confirm that’s the issue.

When I plug the USB in, the internal status led lights up yellow briefly and the display also turns on. It goes through a quick startup and then shuts off (display says “shutting off…”). Pressing and holding the internal power button does nothing.

Boards look clean, antenna has some corrosion and residue upon closer inspection

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The antenna’s top element looks fairly nominal to me - whatever material is used likes to oxidize so that looks pretty normal. I also agree with you though, that RF shield solder seam looks a bit brown. Not sure if it’s flux (it takes a lot to solder those shields) or if it’s water exposure.

Feel free to (gently) detach the antenna’s U.FL connector from the mainboard and try powering on the mainboard. If the antenna is shorting out, that would lead to power problems on the mainboard.

Here’s a couple antennas I have around SparkFun to compare to. Tops look similar. I am wrong about the RF shield soldering, there’s little/no flux on my units so yea, yours is more likely to be water related.

Antenna is removed following documentation. Same problem persists of no response from power button, but a single power on and off cycle due to usb plugin

This is where I cheat and pull out known-good boards and eliminate the unknowns, but you do not have the luxury. I’m happy to take a look to see if it’s repairable. Start an RMA here. If you can return the entire unit (housing and all boards) then we can possibly re-use the housing.

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Thanks, I’ll get the return initiated. Is there any sort of note that I can provide in the RMA to direct the kind folks working on it to this thread? Thanks!

You can put a link to this thread (and a brief explainer) in the " Reason for returning product(s):" field