My Dive Computer Quit



Picture this: you are swimming along an enormous wall in the Caribbean; there is clear blue water above and below you as you drift along in a mild current.  You’re taking time to look at the wide variety of coral and marine life present on the wall, all the while taking moments to change the scene by looking into the abyss to see if any sharks are swimming by in the blue.


Seems like a great dive, right?


Well, we forgot to mention that it’s the second dive of the day, the last time you checked your dive computer you noticed your No Decompression Limit (NDL) was 8 minutes, and the depth was 27MSW/90FSW.  You thought to yourself, “just another minute or two” and I’ll start working my way up to do a nice multilevel dive.

After what seemed to be moments later, you look down to your computer and it’s blank. You tap the screen, hoping it will turn back on or maybe you’re looking for a miracle, but all you see is a black screen, void of information.

It hits you… Your dive computer just died, you’re at 27MSW/90FSW (or so you think), it’s the second dive of the day, and you’re nearing your NDL.  Now what?


First thing, realize this is not an emergency but an inconvenience.  Check your cylinder pressure to verify the status of the best resource you have which is the gas you are breathing.  You realize you have ample breathing gas supply; this is good!  Now you can efficiently work towards a solution.


We should note since your dive computer is a required piece of equipment (no different than your mask and fins), it’s important to understand if it fails; the dive is over, period. No questions asked.

Calmly signal to your buddy or team, “end the dive” by giving the “thumbs up” hand signal. Point to your computer so they see it’s dead and work your way shallow together.  Your dive buddy has a resource you do not have – a way of monitoring ascent rate and depth, so stay together.


Sticking together will help ensure you follow a controlled ascent to 15-20FSW.  Once you get there, its advised to do an extended safety stop (gas permitting) since you cannot be certain you did not go over your NDL.  After surfacing, let the dive crew (if present) know what happened. They will likely suggest you sit the next dive out and take a break from diving for the day.


So how can we avoid this from happening again?


Strive to be proactive versus reactive.  During your predive checks (ABCDE), remember the “C” stands for computer.  When you’re checking your computer during your predive checks, verify your dive computer is on, set to the right gas, and you have battery power sufficient for the dive.  If not, change it out.  Also, if your dive computer requires batteries, carry extra so you’re never tempted to push its battery life.


Expand your tool box and resources by carrying a backup timer and depth gauge or secondary dive computer; this will allow you to monitor depth and time as a backup to your primary dive computer.  You can also store a set of air dive tables in your pocket to reference during a dive, if needed. If you’re diving nitrox this will add in some conservatism to your dive.


Remember, if your dive computer fails, stay calm. It’s not an emergency; it’s an inconvenience. Being proactive versus reactive will reduce the chances of this happening on future dives.  For more information on dive computer considerations or secondary computer options, contact your local SDI dive center near you.