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12c won't turn on --- options?
Message #1 Posted by gene wright on 27 Oct 2011, 12:21 p.m.

It has good batteries. What are the resurrection steps to try?

This is a single 2032 battery non-12c+ made in China a few years ago.

Not worth major surgery :-) but thought it would be good to try a couple of things.

So, batteries are NOT the problem.

Next? :-)

      
Re: 12c won't turn on --- options?
Message #2 Posted by Kerem Kapkin (Silicon Valley, CA) on 27 Oct 2011, 12:27 p.m.,
in response to message #1 by gene wright

Gene,

Can you check the current drain, idle (no power), button pressed, etc? It may give an indication of any anomaly and narrow down possible fixes.

-Kerem

      
Re: 12c won't turn on --- options?
Message #3 Posted by Thomas Radtke on 27 Oct 2011, 12:39 p.m.,
in response to message #1 by gene wright

All keys 'click'? If one makes permanent contact, it wouldn't turn on.

      
Re: 12c won't turn on --- options?
Message #4 Posted by Egan Ford on 27 Oct 2011, 1:00 p.m.,
in response to message #1 by gene wright

Perhaps contrast is down. Stuck key?

Edited: 27 Oct 2011, 1:00 p.m.

      
Re: 12c won't turn on --- options?
Message #5 Posted by Katie Wasserman on 27 Oct 2011, 3:52 p.m.,
in response to message #1 by gene wright

Did you remove the battery and short the contacts inside the calculator together for a few seconds?

            
Re: 12c won't turn on --- options?
Message #6 Posted by gene wright on 27 Oct 2011, 4:00 p.m.,
in response to message #5 by Katie Wasserman

-- No stuck keys

-- yes, shorted the internal contacts with a coin and then with a paper clip.

Might just be dead, but thought I would hunt for magic tricks.

      
Re: 12c won't turn on --- options?
Message #7 Posted by db (martinez, ca.) on 27 Oct 2011, 8:18 p.m.,
in response to message #1 by gene wright

are the feet and battery door in good shape? use it for parts.

      
Re: 12c won't turn on --- options?
Message #8 Posted by Randy on 27 Oct 2011, 11:08 p.m.,
in response to message #1 by gene wright

Not sure the age of the unit you have but a very common problem with early one cell 2032 units was a really *bad* design in the battery contacts.

The + contact on the left side gets bent out of position, failing to make contact. Remove the cell and look for the contact to protrude into the circular area taken up by the cell. If you don't see the contact while looking straight down into the cell area, that's the problem.

FWIW, the design was later modified.

            
Re: 12c won't turn on --- options?
Message #9 Posted by gene wright on 28 Oct 2011, 10:45 p.m.,
in response to message #8 by Randy

For the record, the problem suggested by Randy was the reason it would not turn on.

The small contact that touches the side of the single 2032 battery cell was not bending out enough into the cell receptacle to make contact with the battery.

A slight amount of bending and it made contact.

Voila. A working 12c.

Thanks all.


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