Fault d:5C81 appears when i try to take picture on my E:400.Any ideas

Sounds like backlight inverter problem. Check and replace damaged components, if any. If you wish to get some details; check the site linked here. Pull up older posts.
https://electronicshelponline.blogspot.com/
https://elektrotricks.blogspot.com/
faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent. Search the site by type in the brand name of your set, in its search bar at the right side column, and press enter.

Sounds like main board fault. If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/
Faults & possible causes to LCD screen are given with illustrations. You can get an idea about the fault to an extent.

Yes,this tv it is repairable,ur tv it is having a problems with a 1 or 2 long boards that are call the LCD inverter boards.These 1 or 2 long LCD inverter boards only job it is to provide the LCD screen panel a backlight to produce a picture.Tries websites like Shopjimmy.com,Ebay.com to buy those 1 or 2 long refurbishes LCD invert boards for the replacement.

Sounds to me like you are trying to see a TOPO picture using the Basemap. Assuming that you have TOPO maps the terrain should appear at the 3 miles:1 scale and lower.

This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check this link for more info.
Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110, IXUS V2/V3/300/400/430/500/II/IIs, IXY Digital 200a/300a/320/400/450/500/30/30a

This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check the following two links for more info:
　
http://camerarepair.blogspot.com/2007/11/canon-digital-cameras-showing-black.html
　
http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&fcategoryid=225&modelid=13390&keycode=2112&id=29819
　
Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110, IXUS V2/300/400/430/500, IXY Digital 200a/300a/400/450/500

This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check the following two links for more info:
　
http://camerarepair.blogspot.com/2007/11/canon-digital-cameras-showing-black.html
　
http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&fcategoryid=225&modelid=13390&keycode=2112&id=29819
　
Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110, IXUS V2/300/400/430/500, IXY Digital 200a/300a/400/450/500

This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check the following two links for more info:

http://camerarepair.blogspot.com/2007/11/canon-digital-cameras-showing-black.html

http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&fcategoryid=225&modelid=13390&keycode=2112&id=29819

Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110, IXUS V2/300/400/430/500, IXY Digital 200a/300a/400/450/500

i had this problem with my camera the same make it happened twice and E18 appeared both times its a fault with the lens its has been knocked out of place and thats why it will not close mine was because it was dropped on the floor with the lens out! i blagged to the company that i brought it from that it just happened and they swapped it for a new one both time in the shop. its worth a try

I found the same fault, but for me it is intermittent. I have tried all sorts of things to clear it, but the best seems to be leave it turned off for a while. I bought my Ixus 400 in Sept 03 and the fault started in Jun 07. It shows already taken pictures with no problem on review on the LED screen, but the screen blurs (with motion) and records that same blurred image.