Re: Front heated windscreen wiring
"Chris Whelan" <firstname.lastname@example.org> wrote in message
> WTB wrote:
> > After getting my old window replaced I now have a heated screen fitted
> > however need to wire it up.
> > Does anyone have wiring details or any idea of where the connections are
> > on the windscreen?
> With the greatest of respect, this is not a job for the faint-hearted!
> The heated front screen draws more current than anything else on the car
> apart from the starter motor. I believe it is around 40A? When you switch
> it on, the lights dim, the blower fan slows and you can hear the
> whine in protest!
No, its more like 70amps, 35 per side. The wiring exits down the windscreen
pillars into the scuttle area both sides.
> For that reason the screen elements are in two separate circuits. They are
> wired so they can only come on when an "engine running" signal is sent by
> the ECU. At the same time, the idle value in the ECU is increased to keep
> the alternator output high. The software is possibly present in all cars
> whether fitted with a HFS or not, but you would need to confirm this
> you start. I don't think any of the wiring or relays are fitted either.
No, they are not fitted, nor is the wiring, which forms part of the heated
> Others have asked this question here in the past and the general opinion
> been that it is simply too much trouble to retrofit.
> If you decide to go ahead I would urge you to get it done professionally
> unless you feel you have the skills needed. Let us know how you get on.
Yes *very* good luck!!