Cobra 3 Gauge Mode - Don't do it. Also, easy way to remove scratches from protector.

[Robert Gillcash]

Word of warning, don't use the Gauge Mode on your Cobra 3. Be very careful when you are changing from Nitrox to Air that you don't accidentaly put it to Gauge Mode.
This happened to me for a pool session! Geez! In a 9' max depth pool, with students. Using air.
Next, as I am trying to reset it back to Nitrox in preparation for the next days Open Water dives, I cannot.
The Gauge Mode has an automatic 48 (???) hour No-Fly time (It's locked out from doing anything else!!).
Wow, what a pain.
Fortunately, I was able to find a reset program (How to Reset a Suunto Cobra | eHow.com) that was actually able to reset my Cobra 3 back to the factory settings. As I always log my dives in my Log Book (yet another reason to do this!) I only lost one dive info.
Just don't do it.

Next, to clean off those scratches from your screen cover, try some Solvol AutoSol. It works great. It's a great metal polish that will make aluminum shine like a mirror but also works great for polishing plastics like the screen covers and yes, even your car headlights.

 

[Scubakaas]

Thanks for the update and the link to a solution

 

[Peter_C]

My computer hasn't left gauge mode since I got it. Why wouldn't someone with your experience just use tables?

 

[eelnoraa]

That's the way most computer is. Once it is in gauge mode, it can't switch back to computer mode for a period of time, not unique to Cobra

 

[Peter69_56]

For those who are unaware; done for a reason too. The computer looks at your accumulated Nitrogen loading over a number of days and so if you do repetitive dives its calculating the overall nitrogen loading to work out No Decompression Limit. So if you go diving say for 2 days 2-3 dives per day and then accidentally go to gauge mode, then use the reset function to get back to computer mode, you have taken away all the information relating to previous dives and Nitrogen loading. The computer assumes you haven't dived at all for weeks and uses an incorrect calculation. Thus you may exceed your nitrogen loading on the next dive even though your computer shows all is ok. This has the potential to cause the bends etc. Care must be taken when resetting a computer manually from gauge mode. In saying that, I would think as long as you didn't push your next dive, if you reset from a pool dive the risks would be very low in having issues. However its worth remembering if you accidentally change to gauge mode with deeper dives. My computer only waits 24 hrs before resetting, obviously some are more conservative than others. Forgot to also say, met a young guy who was using the reset function to completely reset his computer after he was exceeding his computer limits causing it to lock up. Instead of heeding the computer warnings to not dive again that day for 24 hrs, he simply either reset the computer and dived again or used another computer. Extremely stupid as the computer had no information as to his very very high Nitrogen loadings. He did say he sometimes came out with pains, but when I tried to discuss it further with him he simply shut down and walked away not wanting to hear the risks he was exposing himself to.

 

[Hatul]

Good warning. As far as the Suunto plastic protectors, I found a much better solution is Zagg protector, which results in markedly improved readability.

 

[Robert Gillcash]

My computer hasn't left gauge mode since I got it. Why wouldn't someone with your experience just use tables?

I teach the tables as part of my classes, but only because I need to. If I had a choice I would never use or see them again. PADI has recognized the usefulness of dive computers since the year 2000.
Tables are too limited. I have fun in my classes when I temporarily promote all my students up to my level, and then ask them to plan a dive with me to 102'. How long can you stay down? 16 minutes. Not very long huh?
Then I show them a graphical chart of a dive I did a few years ago, in BC, cold water, strenuous conditions, where I dove to 102' and spent over an hour total underwater diving. 62 minutes actually.
Try doing that with the tables. Good luck. My computer tracks my air consumption and my nitrogen loading, allowing me a good, safe, conservative dive at all times.
The BIG reason I have a problem with the table is that virtually all divers I see who are not using computers don't even have their tables with them! They use them for their first or second dive, then leave them in the car for the next 10 or so, then leave them at home. So how do they help? Simple, they don't.
A dive computer goes with them on every single dive. It keeps track of time automatically, no forgetting to start and stop your stopwatch. It keeps track of your surface interval, no forgetting to start and stop your stopwatch. It tracks all your dives.
Take a look, a close look at the divers out there who aren't using computers. I'll bet that the majority don't even have a watch to track their time, or if they do, they don't actually use them to time their dive. Nor do they use the tables to plan or track their dives.
Yeah, tables are good. For drawing straight lines with. That's about it.
Dive computers are the way to go. Sort of like comparing automatic cars to manual shift. Probably notice that the overwhelming majority of cars are automatics now. Except the really cheap ones...like the tables.

 

[Scared Silly]

It would be helpful for computers to have a confirm when going into gauge mode - that would prevent issue like the above. Especially, when there is loading on the tissues.

 

[hscohen]

It would be helpful for computers to have a confirm when going into gauge mode - that would prevent issue like the above. Especially, when there is loading on the tissues.

That's right! The Cobra seems to be particularly vulnerable to accidental switching from Air or Nitrox to Guage. A little accidental pressure on a button can do it. I do a lot of diving on liveaboard boats-- 3 to 5 dives a day for a week or more. I've been bitten this way by my Cobra on two trips. The head divemaster on my last trip (Raja Ampat) told me that he rarely has a 10-day cruise without one diver getting the accidental reset.
Now, you've just spent a gazillion dollars to make a lot of dives in some magical far-away place, and you can't use your computer for 48 hours. If you reset it, you lose the nitrogen loading memory, which is really dangerous when you've been doing many dives each day. I carry a cheap Mares Puck on every dive as a backup, so I've still got a computer with the correct nitrogen loading.
But the correct solution would be for Suunto (HEY SUUNTO!) to modify the stupid user interface software so that you can't leave Nitrox mode or Air mode without explicitly confirming that you really want to.

 

[Morgan Fish]

I know this thread has been inactive for a while, but out of curiosity, does anyone know if you are able to change dive modes once you're underwater? Or is this just a concern as you're using the Cobra to plan your dive while you're on deck waiting to get in? Sucks either way, but I definitely don't want to mess it up while I'm down. Thanks!