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No heated rear screen on 944S2
https://forums.tipec.net/viewtopic.php?f=25&t=2328		 Page 1 of 2
Author:  steveh [ Mon Dec 08, 2008 1:32 pm ]
Post subject:  No heated rear screen on 944S2
When I switch on the heated rear screen the light on the switch comes on but the heater doesn't work. Neither do the heated front screen nor the rear view mirrors which I assume are on the same switch, this is a problem on these cold and frosty mornings!

I have checked the fuse and that seems OK and so does the wiring, so I would be grateful for any suggestions as to where to look next? is there a relay that covers these things?

Thanks in advance for any help

regards

Steve
Author:  Scho [ Mon Dec 08, 2008 2:22 pm ]
Post subject:  Re: No heated rear screen on 944S2
the screen is wired through you're tailgate struts. check they are connected as mine come loose from time to time. it could also be you have aftermarket struts that don't make the connection so check that out too.
Author:  steveh [ Mon Dec 08, 2008 3:08 pm ]
Post subject:  Re: No heated rear screen on 944S2
Scho wrote:
the screen is wired through you're tailgate struts. check they are connected as mine come loose from time to time. it could also be you have aftermarket struts that don't make the connection so check that out too.

Thank you, I've checked the struts and they seem OK but I will clean them up with WD40, this wouldn't explain why the other two heater elements don't work.

Steve
Author:  David924S [ Mon Dec 08, 2008 4:48 pm ]
Post subject:  Re: No heated rear screen on 944S2
There is a relay at position G3 under the bonnet in the main fuse box which is operated from the switch via the fuse I would check this relay is working.
Author:  J.J. [ Mon Dec 08, 2008 5:47 pm ]
Post subject:  Re: No heated rear screen on 944S2
Didn't know these had heated front screens. Is it just the S2 or do other models? Mines had a new screen so it should work if it's got one. My new (Old) rear screen works ok as do the mirrors. Usualy I end up sitting in it for five minutes while the heater does it's thing.
Author:  lindsayhbrown [ Mon Dec 08, 2008 5:54 pm ]
Post subject:  Re: No heated rear screen on 944S2
J.J. wrote:
Didn't know these had heated front screens. Is it just the S2 or do other models? Mines had a new screen so it should work if it's got one. My new (Old) rear screen works ok as do the mirrors. Usualy I end up sitting in it for five minutes while the heater does it's thing.


its just a blower on thw front screen
Author:  PaulSmith [ Mon Dec 08, 2008 6:53 pm ]
Post subject:  Re: No heated rear screen on 944S2
They are three seperate systems.

1. As said already, the HRW is supplied through the tailgate struts and non genuine struts often do not work. Also the flexi wires from the struts to the screen are often brittle and corroded, worth replacing with some new wire of the correct ampage.

2. The rear mirrors are always heated as soon as the ignition is on. If they don't heat then you have a wiring problem or more probably the heater element in the glass has burnt out. New mirrors from Porsche have the element built on to the back and cost roughly £50 each

3. The button on the dash simply switches the hot air to full blast and closes all the vents except those to the screen. It also switches the blower speed to number 4. If your car is not up to temperature yet it simply blows lots of cold air at the screen
Author:  tr7v8 [ Mon Dec 08, 2008 7:51 pm ]
Post subject:  Re: No heated rear screen on 944S2
PaulSmith wrote:
They are three seperate systems.

1. As said already, the HRW is supplied through the tailgate struts and non genuine struts often do not work. Also the flexi wires from the struts to the screen are often brittle and corroded, worth replacing with some new wire of the correct ampage.

2. The rear mirrors are always heated as soon as the ignition is on. If they don't heat then you have a wiring problem or more probably the heater element in the glass has burnt out. New mirrors from Porsche have the element built on to the back and cost roughly £50 each

3. The button on the dash simply switches the hot air to full blast and closes all the vents except those to the screen. It also switches the blower speed to number 4. If your car is not up to temperature yet it simply blows lots of cold air at the screen

Item 2. I always understood the heating on the mirrors was linked to the HRW?
Author:  Li Moo Bai [ Mon Dec 08, 2008 8:05 pm ]
Post subject:  Re: No heated rear screen on 944S2
tr7v8 wrote:
PaulSmith wrote:
They are three seperate systems.

1. As said already, the HRW is supplied through the tailgate struts and non genuine struts often do not work. Also the flexi wires from the struts to the screen are often brittle and corroded, worth replacing with some new wire of the correct ampage.

2. The rear mirrors are always heated as soon as the ignition is on. If they don't heat then you have a wiring problem or more probably the heater element in the glass has burnt out. New mirrors from Porsche have the element built on to the back and cost roughly £50 each

3. The button on the dash simply switches the hot air to full blast and closes all the vents except those to the screen. It also switches the blower speed to number 4. If your car is not up to temperature yet it simply blows lots of cold air at the screen

Item 2. I always understood the heating on the mirrors was linked to the HRW?


Mee 2 :?
Author:  DavidL [ Mon Dec 08, 2008 8:09 pm ]
Post subject:  Re: No heated rear screen on 944S2
I like the idea that Paul has rear mirrors on his car - just have this mental image of a 944 looking a bit like a lambretta with row upon row of mirrors.
Sorry Paul, I know what you mean really.
I'm sure I read that the door mirrors were heated from the same circuit as the HRW - certainly that seems to be the case on mine these last few mornings. Well apart from the drivers one that doesn't work.
Author:  hotblack944 [ Mon Dec 08, 2008 8:49 pm ]
Post subject:  Re: No heated rear screen on 944S2
PaulSmith wrote:
2. The rear mirrors are always heated as soon as the ignition is on.

I think that's true of the cab (no HRW switch!)
Author:  PaulSmith [ Tue Dec 09, 2008 7:29 am ]
Post subject:  Re: No heated rear screen on 944S2
hotblack944 wrote:

I think that's true of the cab (no HRW switch!)


OOps - you're right :oops:

I just reread my owers manual and the door mirror heaters in the coupe are controlled by the HRW switch.

Cab has no HRW switch and they are always on.
Author:  steveh [ Tue Dec 09, 2008 7:37 am ]
Post subject:  Re: No heated rear screen on 944S2
Wow, Thanks for all this, I guess my first port of call is the relay. The reason I thought there was a heated front screen is because there is a black line that looks like a heater element that runs around just the drivers side of the windscreen, if it isn't heated I wonder what it is?

Steve
Author:  zimm [ Tue Dec 09, 2008 8:05 am ]
Post subject:  Re: No heated rear screen on 944S2
radio aerial
Author:  steveh [ Tue Dec 09, 2008 2:56 pm ]
Post subject:  Re: No heated rear screen on 944S2
Well, I have found out why nothing works, the G3 relay is completely missing! I have ordered one but why would someone remove the old one? should I look out for anything when I install the replacement?

Thanks

Steve
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