Cobalt won't turn on. Screen is black

[Chris Wik]

Thank you, I kept trying with the 11 + second Back-Select button press, I was not sure it was getting charges, so I plugged it in wen I did the 11 + second Back-Select button press, did it a few times and it finally worked, after messing with it for a bit, I realized the select button is very glitchy. When I get back from my dive trip. I will address the magnet problem. Can that magnet be replaced if it is the problem?

 

[RonR]

Thank you, I kept trying with the 11 + second Back-Select button press, I was not sure it was getting charges, so I plugged it in wen I did the 11 + second Back-Select button press, did it a few times and it finally worked, after messing with it for a bit, I realized the select button is very glitchy. When I get back from my dive trip. I will address the magnet problem. Can that magnet be replaced if it is the problem?

If there is time, I would strongly recommend that you fix this button issue before your trip. It's very easy to check out and do. Popping off the top cover as in the instructions I linked above should show you if there is corrosion on the magnet- if so, it's possible other magnets are in the same situation. The magnets just pop in and out. I've seen situations where a button magnet is failing, and goes out completely when you start diving with it. You can use the Cobalt without the Up or Down buttons (in diving, Up only is used to manually initiate a gas switch), so it's possible in a pinch to swap one of them with a problematic Back or Select button magnet and just live with extra scrolling.

Knowing your serial # or the date of manufacture would help me know if you are in the time period when magnets were not being fully encapsulated. I'll start an off forum "conversation" with you to get contact information and get you newer, fully encapsulated magnets if that turns out to be the problem.

-Ron

 

[scuba-prof@msn.com]

If the adapter was left plugged in to the Cobalt (but not charging) it's most likely the battery is drained. Leaving the adapter in is the same as being submerged in water, the Cobalt goes into a standby/ ready to dive mode that uses more power than normal sleep mode. It could drain the battery from a 60% charge in a couple of days.

The solution is to charge the Cobalt to bring the battery back up- it will be charging even if you don't see anything on the screen, then do a reboot/ turn on by holding down the Back and Select buttons for 11 seconds. From what you say I'd guess there is nothing wrong with your Cobalt other than not having any charge in the battery.

Ron

 

[scuba-prof@msn.com]

Ron,

How long might it take when plugged in to the AC adapter for my Cobalt 2 to recover from a fully discharged battery? I've had mine plugged in for the past 12 hours. The reboot process does not cause the unit to turn on.

 

[RonR]

Charging from a fully depleted battery shouldn't take much more than a couple of hours. And it should be possible to reboot the computer within just a few minutes. If the USB charging side of the adapter is being used you have to remove the adapter before rebooting, otherwise the Cobalt goes into a mode where it is looking for a firmware update. But you are connecting to the A/C side of the adapter,so that would not apply.

I would try the steps I laid out in Post #30 of this thread- just a few posts above, and let me know what you find. The age or serial # of the Cobalt is also helpful, as is the firmware version.

It's possible if a battery is left discharged for a very long time it could be damaged, but it's unusual for one to be so weak it won't boot up the Cobalt.

-Ron