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EOS-1D Mark II won't recognize NP-E3 battery


Hi, I am working on an old old original Canon NP-E3 battery
that's in need of identifying the name of a defected component so that
a replacement may be procure. I am thinking this is a fuse or
something. At this point the camera (1D mk2) does not recognize
the battery even with the fact that the battery is fully charged up
(13.2 V) and keeping the charge.

Back to 2008 when this battery showing signs of ageing (not
charging or depleted quickly) I put it aside and purchased a third
party HQRP replacement happy ever since. The Canon unit has been
on the shelve all these years. Yesterday I took the NP-E3 out
wondered what I should do about. In the beginning I thought individual
cells were no good. I've read much about battery replacement and
thought that's what I will do. Last night, thinking I've got nothing to
lose, using a NC-E2 I refreshed and recharged it many rounds, amazingly,
it reached 13.2 volts and holding. Sadly,when inserted the camera did
not recognize it. Not power up.

What I've done to it previously (in 2008) is opened it up removed
the fuse resistor (I thought that's what went wrong) tested for con-
tinuity forgot to solder it back lost it eventually.

I've included here a photo of the part that's missing from the battery
compartment. If you know what that is please let me know. Thank
you ! Thank you !!
canon np-e3 11.jpg



Think I've found out lately that this is a thermo fuse triggers at
93 degree C. I already placed an order for it hopefully will
come in soon. The voltages measured from the two terminals settled
at 12.86 volts after two days so I am sure each of these ten cells
all in good working order and needs no replacement. Thanks for
all your help and reply I appreciate that very much.

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