Old computer algorithm question

[BKSZEA]

I have an old Oceanic Datamax Sport that I've had for years and I just noticed something odd about the no decompression limits that scroll at startup. I'll list these below and then continue with the post.
30ft 2:40
40ft 1:21
50ft 53min
60ft 36min
70ft 27min
80ft 20min
90ft 16min
100ft 12min
110ft 09min
120ft 08min
130ft 07min
These don't match up with the NDL's in the computer manual, (significantly shorter) or with any of the other Oceanic computers I have. It's as if the computer has a pre-set N2 loading and is giving less bottom time for each depth, but the tissue loading bar graph starts at zero when powering the computer up. I only use this one as a depth gauge anymore, but at least it would be on the conservative side if used as a computer.
Anybody have an idea what might be going on here? These computers aren't adjustable as far as I know.

 

[KeithG]

Maybe the pressure sensor is off just a bit? I dug an old uwatec Aladin sport out of a drawer (to check its plan) and it is displaying a mountain symbol on the main screen. This seems wrong?

I have failed miserably at downloading an Uwatec manual on my phone so I am just guessing you may have the same problem?

What effect do you expect from high altitude dives?

 

[scrane]

My ProPlus2 gives me almost the exact same scrolling NDLs because it is stuck in the second altitude group (3001-4000 ft altitude). Compare your scrolling numbers with the chart in your manual. I have found no solution to this problem.

 

[tursiops]

You should be able to reset the altitude setting back to sea level. OP, is there a little mountain symbol somewhere on the screen?

 

[scrane]

How would you reset the altitude level? I think it's automatically controlled by the pressure sensor.
This seems to be kind of a common problem with Oceanic computers.

 

[scubadada]

@BKSZEA

As others have said, you have a faulty pressure sensor. Your NDLs actually reflects 6001-7000 feet of elevation. The computer is very old and not supported by the Oceanic factory service program for out of warranty instruments. Probably, the best you could do is trade it in for 20% off the list of a new Oceanic computer.

 

[BKSZEA]

Thanks for all the input. For everyone's info, there is no mountain symbol on the screen, and I tried removing the batteries for a while to "reset" it, but no luck. So just as I has suspected, its going to be used as a paperweight in the future. Thanks again!!