I have a Rover 25 and the rear screen demsiter isn't working, how can I fix it?

Question

It's not the fuse and I can't see anything obvious with the screen itself and I'm at a loss as to how to fix it

Answer 1

Check where the wires meet the window, see if they are still connected. if they are pull the wire off the connector carefully, get a electrical tester and check the electrical supply.

If you don't have a tester, get:

two lengths of wire, ends bare.
A car lightbulb.
Some blue tack.

Connect one end of first peice of wire to bottom of light bulb with blu tack, and the other peice of wire, blue tack to side of lightbulb terminal.

so you have a very basic circuit tester. one end goes into the connector on one side of window, the other end goes into connector on the other side of window, turn on the rear demistor, (it won't give you an electric shock, or set on fire, i promise!) and see if the lightbulb lights up. if it doesn't, then you have a supply problem, so check back thru the system till you get a supply.
If it does light up at the window, then you have a break in the element, common enough for car maintenance places like motorworld and halfords to sell little pen things to fill in the gaps. the gaps can be miniscule so get the magnifying glass out.

Also, some car maufacturers, more than likely including Rover, will cut corners to save costs, (they did go bust after all), the book might say, for example fuse 15 is for the demistor, but it has been known to be a different fuse, or a bit of dodgy wiring, meaning a different fuse is doing the job, so check every fuse first.
It is fairly unlikely that only the demistor is on the same circuit regulated by the fuse, so something else may not be working as well, check every single electrical item, including silly things like ashtray light, glovebox light, etc.

Good luck.

Answer 2

Hi there, Rover 25 are bad for the wiring splitting where it comes through from the shell near the hinges, you will see a rubber corrogated looking hose, try there and also check fuses and contacts at window itself. Hope this helps.
Cheers

Answer 3

check to see if theres an electrical relay usually by the fuse box ,these do pack in at times ,heated rear windows are usually on a timer so may be a second timer relay as well.