My rear window misted up for the first time yesterday and I found that quite a few bars/elements did not work.

Can this be remedied?

Any suggestions welcomed

Each bar is a line of conductive paint, and as the electricity passes through it becomes warm and defrosts the window

Some of the lines will have a break in them, where some of the paint has come away. This means the electricity cannot get through, and so these lines do not get warm.

The window is designed so that if some lines are broken, the rest still work

You can fix the problem by repairing those broken lines. Halfords sell a special paint for this, which has tiny metal particles in it so that it conducts electricity.

http://www.halfords.com/webapp/wcs/stores/servlet/ProductMobileDisplay?catalogId=10151&storeId=10001&productId=203667&categoryId=255229&langId=-1

You may be able to get it cheaper, eBay for example.

You just need to re-paint the broken sections, so that the electricity can get through.

You don't need to do the full line, just the section that has worn away. This may be just an inch long.

Mask it very carefully with tape first, so that the new lines are no thicker than the existing lines

Thanks, that Halfords information is what I was looking for.

Looks like being difficcult detecting the breaks - have found three not more than a couple of mms long, and there are more somewhere - and this weather is not very conducive to that type of job

My rear window also has these breaks, on three lines

I can see a change in colour where the breaks are : the working section is a dark brown colour, the damaged section is more of an orange colour.

Maybe placing white paper the other side of the glass will help to make this colour change stand out more?

I suspect the window lines are applied with a two-layer process - a base layer (the orange line I can see in some sections) and a conductive layer on top of that (the brown line that's broken and missing in some areas?

Perhaps you can see the same colour change on your window?

The Halfords stuff gets mixed reviews on the Internet, some people saying it doesn't conduct (and therefore doesn't fix the problem)

Maplins do a similar product that's designed to make/fix circuit boards, which should work on your window. It's only small tube though, so mask up carefully so you don't waste it

http://mobile.maplin.co.uk/module.aspx?moduleno=36275

This website has lots of useful information: instructions, guides, videos etc

http://www.frostfighter.com/

They recommend that repairs are not done when it's cold, as this slows down the curing process. Using a hair dryer can help though.

well worth fixing ive found in the past the halfords stuff did work if applied correctly and not whack it on and leave it like most do with this really cold weather expect more misting up as youre warm body gets into the car and when you park it up overnight 28 degree heat inside the car and -2 outside means misting is inevitable as the hot air hits the freezing window overnight

Maybe the negative reviews for the Halfords stuff are from people who didn't follow the instructions properly?