Heated Windscreen

[Caff]

Further to my last posting my heated windscreen has been replaced but I have more queries!

 

My first screen had no problems with heating elements for several years and was replaced because of a massive crack. I suspect however that this was also a replacement as there was a little glass here and there when I first bought the car when it was a year old. Two subsequent replacements have had heating elements fail within a year of fitting. I am now on a fourth screen.

 

I had a chat with the fitter and he wondered if there was a fault with the relay which controls the screen. Several elements were burnt out across the screen in a random pattern on both sides. He thought a faulty relay could allow too much power to the elements which could then fail and the remaining elements then would get too much power, the whole thing slowly breaking down.

 

He admitted he wasn't sure, he's not an electrician and it was only a theory but as I don't have a clue either I thought I'd ask you knowledgeable folks.

 

Is his scenario a possibility? What exactly does the relay do. I know there is a time element but am unsure of what else. I have a horrible feeling that this relay is expensive and hidden away somewhere difficult but changing screens this often is ridiculous no matter who is paying.

 

Your advice would, as usual be most welcome.

[edatelder]

The relay cannot "provide too much power" to the screen heater. The voltage supplied is always 12 - 15 volts, the resistance of the screen elements will determine how much current and hence, power it draws. This has been posted before. Probably a poorer quality replacement screen than Ford use.

[seatkid]

It may be a second hand screen that was fitted.

 

When my 6 month old Corsa was rear ended, it had a new tailgate fitted. After a week or two I noticed 3 elements not working. Dealer tried to fob me off with "wear and tear" (!!!) and "It was fitted by RAC windscreens go and see them".

THe guy at RAC windscreen was very helpful - they did not fit and could prove it and on close inspection, he found the original screen had been removed from the damaged tailgate and fitted in the new. In the process of cutting back the seal, somone had damaged the screen printed elements and you could see bothe the cutting marks on the glass and where they had painted the glass to cover the damage. Dealer admitted and changed the screen.

 

Do a close inspection of the elements looking for the breaks and then check the ends for damage/evidence of cutting.

[Richard gal]

I had a mondeo one fitted, (new replacement), made by pilkington, after 2 years half the elements in random places had given up, they dont make them like original equipment it seems.

[Caff]

Thanks for those thoughts. As far as I know the screens were brand new fitted by a supposedly very reputable mobile windscreen replacement service that all the insurance companies use. It seems strange that two have become faulty each within a year. The last screen was a Clearvu one. This new one is a Pilkingtons.

I searched the forum for help on this subject and couldn't find anything. Maybe I searched the wrong words.

[Scorpiorefugee]

I agree with RichardGal, I've had 2 screens fitted to Granadas and both lost elements quite quickly. Since the wires are between the glass sandwich there is no point in looking for cut marks but I should not be suprised if it was damage caused by bad handling. i.e. in stock movement and in and out of vans etc. It is also probable that they are not as good as the originals. Certainly, there is no point in worrying about relays as they simply switch the power on an off. As a windscreen rapidly loses its new appearance I doubt anyone could get away with second hand although they must be pretty expensive items.