Laurens,
If any water has gotten into the Cobalt interior the electronics will not be repairable. Even if they could be brought back up, they would no longer be reliable. Your Cobalt sounds like a candidate for replacement.
You don’t say when or where you purchased the Cobalt or how old it is, but this would be a case for warranty replacement. I believe you will find Atomic to be extremely responsive for service and warranty. If you purchased the Cobalt through Atomic Europe that would be the place to go for warranty service.
Kontaktieren Sie Atomic Aquatics A problem like this would not be prevented by good care, it’s a problem with a faulty seal.
There were case issues causing leaks with the Cobalt 1 a number of years ago, when the product was first introduced, those mostly involved water getting into the battery compartment. There was a problem with some high pressure seals that actually resulted in a recall, also early in the product life. Atomic has for some time tested each Cobalt 2 prior to shipping with at least 10 wet dives to 50m, and leaks in the Cobalt 2 have been rare. That’s not to say the Cobalt 2 has been trouble free- the first couple of months production suffered a great deal from a batch of depth sensors that were defective from the manufacturer and did not fail until after some period of use- so they got through factory testing and were sold. Cobalts were removed from production for several months until this issue was identified and solved. There were also issues with corrosion in the buttons, these have been definitively corrected. A great many changes were made to the design of the case internally nearly two years ago to go after any identified weak points.
While the earlier Cobalts had more problems than acceptable, I believe what you see with recent Cobalt production- in the last two years or so- is a company that is very open about any problems and very proactive about fixing them, and engages fully on forums like this, rather than a computer than has an unusual number of problems. No product is going to be without some issues, but Atomic has in my view- based on 35+ years in the field- been excellent in dealing with them.
Don’t hesitate to contact me if you have any questions.
-Ron