G1 Fuse Problem - the Cause ?

[Mark_48]

I've had my G1 for several years now and its been good to me and hopefully it stays that way. Recently browsing around these forums I spotted a few threads on fuse problems with the G1 and G2. I did a further search on it to see if I could find anything regarding what causes it and didn't have any luck.

Anyone know if there's a specific reason why the fuse blows? Was wondering if the lens was prevented from extending if this might do it.

Mark...........

[Roumen]

Originally Posted by Mark_48

I've had my G1 for several years now and its been good to me and hopefully it stays that way. Recently browsing around these forums I spotted a few threads on fuse problems with the G1 and G2. I did a further search on it to see if I could find anything regarding what causes it and didn't have any luck.

Anyone know if there's a specific reason why the fuse blows? Was wondering if the lens was prevented from extending if this might do it.

Mark...........

Hi Mark,

There were a lot of such threads here about:
G1 blown fuse (with explanations how to fix it)
G1 loose screw causing short circuit (it is designed to fall down)
http://forums.dpreview.com/forums/re...essage=7429467
G2 "stuck controls": http://dpgallery.com/resource/g2minority/index_e.asp
Just make a search here or at dpreview forums for G1 dead, G2 "stuck controls", etc

Regarding the "G1 loose screw causing short circuit" - it is a very small screw from the board behind the LCD. The plastic cover over is flexible and when you push it with your thumb the cover behind the LCD you just press the board down and that will cause sooner or later this very small screw to fall down. It is designed to fall down! There was only one case when the Canon support (Illinoys) admitted the problem of the "loose screw causing short circuit" and did not charge anything for their service after warranty. Only one such case...

Regarding the G1 "blown fuse" problem - even the problem itself is due to the protection fuse for the Li-Ion battery/charger (such a protection is necessary, otherwise the result would be a burning camera) it seems to me that non-properly design of the in-camera Li-Ion battery charger is a Canon problem (It is not normal about 1 year operation of the original Canon 511 Li-Ion battery found from all the Canon G1 users; Problems such as early deterioration of battery characteristics may occur if the charge voltage and current are not regulated below a certain value.)
Lithium-ion cells have no memory efect and offer extended cycle life when cycled at low depth of discharge - beyond 10000 cycles. Check:
http://www.nexergy.com/Reflib/Lithium_Ion_FAQ.html
There are also resetable fuses:
http://www.littelfuse.com/data/en/Ap...otes/ec611.pdf Application Notes: Circuit Protection for Lithium-Ion and Lithium Polymer Rechargeable Battery Applications
Regarding the fuse - this part is pretty small (3.2mm x 1.5 mm) and it is a cheap 0.10$ surface mount fuse. It is a shame for Canon to charge 150$ for fixing their own design problem.

Other links:
http://www.dpreview.com/forums/read....essage=2587940 Disassembling G2 G2 lens destroyed
http://www.dpreview.com/forums/read....essage=3102324 How to disassemble G2?
http://hunterftp.hunter.com/~dav/ Canon G1 Digital Camera Blown Fuse Replacement
Also the previously deleted very long link "Dead G1 link" - proflex has posted an information how he fixed a similar problem himself (fixing surface mount fuse)::
http://photography-on-the.net/forum/...?TopicID=20217
http://members.optusnet.com.au/~jono...terfacePCB.JPG
Another G1 blown fuse problem "G1 dead....and alive again" with G1 dissassembling pictures:
http://photography-on-the.net/forum/...?TopicID=22409
http://perso.wanadoo.es/civi_/
http://www.photography-on-the.net/fo...ic.php?t=20873 This is how my G1 died and came back from the dead
http://photography-on-the.net/forum/...?TopicID=22409 G1 dead....and alive again
Unfortunately, after the upgrade of these Forums, old message numbers are not available anymore.

Greetings,
Roumen

[Mark_48]

Roumen,
Thanks for all that. I had found some info on all this, but not the specifics as to why it may fail. I'll be busy looking at the links you posted.

Thanks again,
Mark.......