Rear screen heater poor 1989 530i SE

[simon-york]

Hi Guys

I have noticed eveer since I got my E34 that the rear screen takes a long time to demist - probably over 15 mins maybe more. I can see one or two elements look broken, but I thought all the others should clear fast enough.

Could it be an extra fault like starting on the reduced power setting rather than cutting down once the rear screen has been on a while? Thoughts anyone? Are rear screen demisters usually better than this?

TIA for contributions, all suggestions gratefully received.

[Bill R.]

Am radio antenna, the middle 8 are fm and defroster, and the bottom 8 are defrost , if the middle 8 or bottom 8 have a break in the lines it will affect how fast it defrosts. You can buy repair kits that consist of a small bottle of metallic foil paint. Then you use masking tape to mask off each side of the line where a break is and paint a thin line to reconnect it... I used it before to repair defrost elements and broken fm antennas.
http://www.bimmernut.com/%7Ebillr/images/antenna.jpg
http://www.permatex.com/images/catalog/special/15067.jpg








Hi Guys

I have noticed eveer since I got my E34 that the rear screen takes a long time to demist - probably over 15 mins maybe more. I can see one or two elements look broken, but I thought all the others should clear fast enough.

Could it be an extra fault like starting on the reduced power setting rather than cutting down once the rear screen has been on a while? Thoughts anyone? Are rear screen demisters usually better than this?

TIA for contributions, all suggestions gratefully received.

[MantecaBMW]

And while on the subject, my rear defroster doesn't work at all. It was never an issue before as the car was always garaged. All the connections look good and no fuses are blown. Where else can I look for the source of the problem?

Mark

[Bill R.]

rear seat and check the defogger relay k13 under the rear seat
http://www.bimmernut.com/%7Ebillr/images/defogger%20relay.jpg






And while on the subject, my rear defroster doesn't work at all. It was never an issue before as the car was always garaged. All the connections look good and no fuses are blown. Where else can I look for the source of the problem?

Mark

[MantecaBMW]

Thanks Bill. I'll check it tonight and let you know.

[simon-york]

Bill,

Thank you very much indeed for your wisdom. I know of the special paint to repair window elements but I had no idea that some elements are dedicated to the am radio antenna and will never heat up. I shall repair the broken element and see if performance improves. Is it possible that the relay has failed leaving it on 'half power' also? Is this handled by the small box labelled 2 in your second diagram? I know somehow the element is switched to a reduced power setting after approx 15 mins of use
BTW where are these useful diagrams to be found please? Have never seen them on the TSK.

Thanks again,
Simon Daubeney, York, England.


Am radio antenna, the middle 8 are fm and defroster, and the bottom 8 are defrost , if the middle 8 or bottom 8 have a break in the lines it will affect how fast it defrosts. You can buy repair kits that consist of a small bottle of metallic foil paint. Then you use masking tape to mask off each side of the line where a break is and paint a thin line to reconnect it... I used it before to repair defrost elements and broken fm antennas.
http://www.bimmernut.com/%7Ebillr/images/antenna.jpg
http://www.permatex.com/images/catalog/special/15067.jpg