What exact option kills GPS signal reception under windscreen?

[MartiniB]

would like do some research

before select option PKV(Heated windscreen) i asked dealer opportunity to check reception
and didn't noticed any signal drop in dealer's TDI ??? DSG L&K
but in my TSI 220 DSG Style are huge problems with GPS signal reception

 

 

please write here only in case your car got Heated Windscreen

PWC - Lane assist
PNC - Light assist with high beam control Assesses the light conditions and traffic situation
PNG - Smart light assist Uses the multi function camera
PWD - Traffic sign recognition
RAC - Amundsen
RAG - Columbus
PT1 - Phone box By placing a mobile phone in the tray
PT2 - Premium WLAN with integrated high-speed LTE internet
EI9 - SMARTGATE
PLI - ADAPTIVE CRUISE ASSISTANT(160km)
PLG - ADAPTIVE CRUISE ASSISTANT(210km)
PHD - Auxiliary heating

Problematic reception:
Package; Prod.Week; PWC; PNC; PNG; PWD; RAC; RAG; PT1; PT2; EI9; PLI; PLG; PHD; Numbers on Windsreen
 _Style; _ 8W 2016; Yes; ---; Yes; Yes; ---; Yes; Yes; ---; Yes; Yes; ---; Yes; DOT617 M456 AS1, (E8) 43R - 003993, IR-H/A E000234 ∙∙∙∙∙∙ 6

Good reception:
Package; Prod.Week; PWC; PNC; PNG; PWD; RAC; RAG; PT1; PT2; EI9; PLI; PLG; PHD; Numbers on Windsreen
 _L&K _; ~40W 2015; ???; Yes; ???; ???; ---; Yes; ---; ---; ---; ---; Yes; ???; ???...


p.s.
i know, it's completely my problem choosing Škoda after two Audis and one Hyundai

Edited 1 December, 2020 by MartiniB

[dstev2000]

I've got an L&K with smart light assist and the heated screen, and my dash cam is having a terrible time getting a GPS signal. It's mounted directly beneath the sensor/camera pod and I'm assuming it's the metallic heating layer(s) in the screen blocking or attenuating the GPS signal. 

 

There are a few gaps in the heating film in the top of the screen either side of the sensor pod, where the small dots are printed on the screen. I am going to move the camera closer to one of those areas to see if the GPS signal improves. 

 

Failing that, i'll have to get a re-radiating antenna 

[RickTT]

What app are you using ?

 

I can do a compare without heated screen if required.

[Kungfugerbil]

Ok. I have heated screen, lane assist, Columbus - not sure about the rest - standard UK L&K.

I've just compared outside the car with inside next to the screen:

Inside:

Outside:

So slight signal degradation but not much. For a test I did the same in my wife's Hyundai (no heated screen) and it showed a broadly similar amount of attenuation.

Edited 14 April, 2016 by Kungfugerbil

[Kungfugerbil]

What app are you using ?

App is "GPS Test" on Android

[Chorlton]

I think it's heat reflective windscreens that kill GPS signal.

 

My old clio had a patch of screen (middle bottom edge) without the coating where you could stick your NAV to the windscreen

[dstev2000]

I've just been out to the car with an iOS GPS app that shows signal strength. Outside it shows as 'Excellent' with a horizonatal accuracy of less than 5m.

 

I removed the camera and stuck my phone in the same position and the signal strength dropped off to 'Good' with a horizontal accuracy of over 10m. It read the s

I moved the phone up to the top of the screen with the printed dots and it instantly shot up to 'Excellent'.

 

There is definitely something interfering with the GPS there. Is it the heated screen? or perhaps interference emanating from the sensor/camera pod? it doesn't take much to upset a GPS signal as it's very weak anyway. 

I'll try it again with the ignition switched off as my camera is hard wired into a PowerMagic Pro.

[FelisBengalensis]

I think it's the metallic layer. Looking at the 'dotted zone' at the top of the screen, it appears to have a slightly clearer area close to the top The GPS in the dashcam has no trouble at all as it up close to this area. The Garmin nav however is resting on the Canton centre speaker and the signal is much weaker. I frequently get 'Poor GPS Reception' messages and the location drifts. Unfortunately I can't connect an external antenna and place it high up.

Switching from a buried-wired to metal-foil based system may have improved the vision but it is a Faraday cage as far as GPS goes.

Mine has TSR, Auto lights, auto main beam, heated screen, auto-wipers. It was built in early October 2015.

[dstev2000]

I've been out to the car - again - and experimented with the GPS lock on the dashcam and the position on the windscreen. The results are a bit random at the moment so I have no conclusion as yet. 

 

I will move the camera up nearer one of the small 'windows' at the top where the screen doesn't heat. I am presuming this is to allow autotoll tags to work properly as they are pretty common on the continent it would seem. I'll report back when I have more concrete evidence. It could be that my camera is dodgy, or the camera is at or just below its GPS lock threshold in its current position. 

 

This needs a little more investigation.........

[MartiniB]

1. I think it's the metallic layer.

2. Looking at the 'dotted zone' at the top of the screen, it appears to have a slightly clearer area close to the top

 

1. the main point is, there is possible Heated Windscreen without GPS signal drop, i have tested in another Superb and Passat too

2. same in mine

 

now i'm waiting for window id code of that unique L&K without signal problems,

but all requests sent to dealer comes back only after 7-10 days :(

 

if part id will be same then we have exciting lottery

[laaban]

I am presuming this is to allow autotoll tags to work properly as they are pretty common on the continent it would seem.

Spot on. The dotted area is where to adhere the toll tag to secure reception.

[MartiniB]

What app are you using ?

 

I can do a compare without heated screen if required.

no problems in that case, you have to pay 250euros for lottery ticket

 

i'm almost sure there will be zero customers who will select that option if it had warnnig about GPS/GSM signal isolation.

That option adds comfort for less than 1% of car's life while in other 99% comes only problems, especially mine has Auxiliary Heating

 

[Kungfugerbil]

i'm almost sure there will be zero customers who will select that option if it had warnnig about GPS/GSM signal isolation.

That option adds comfort for less than 1% of car's life while in other 99% comes only problems, especially mine has Auxiliary Heating

The flip side is that I think it's brilliant, have had no issues with GPS or GSM, use the excellent built in nav and aux heating isn't something I would want or need.

Many factors affect GPS signal strength and your results from an ad hoc test some time ago in a different car are not representative - the only way that coul be considered as meaningful is if you perform it again - with just the two cars in the middle of an open area and test within seconds of each other in exactly the same place in the car and exactly the same spec of car.

I'm not saying that the reflective windscreen doesn't affect GPS signal - a thin metal film between the device and sky will affect it for sure - but I think your conclusion that different examples of the same heated screen have radically different properties is erroneous.

[MartiniB]

use the excellent built in nav

sorry, but any builtin navigation can't surpass online systems as Waze and Google Map

[MartiniB]

@ALL

please share id numbers on Windscreen, some options tried to gues

 

PWC - Lane assist

PNC - Light assist with high beam control Assesses the light conditions and traffic situation

PNG - Smart light assist Uses the multifunction camera

PWD - Traffic sign recognition

RAC - Amundsen

RAG - Columbus

PT1 - Phone box By placing a mobile phone in the tray

PT2 - Premium WLAN with integrated high-speed LTE internet

EI9 - SMARTGATE

PLI - ADAPTIVE CRUISE ASSISTANT(160km)

PLG - ADAPTIVE CRUISE ASSISTANT(210km)

PHD - Auxiliary heating

 

Problematic reception(MartiniB; Dstev2000;  FelisBengalensis):

Package; Prod.Week; PWC; PNC; PNG; PWD; RAC; RAG; PT1; PT2; EI9; PLI; PLG; PHD; Numbers on Windsreen

 _Style; _ 8W 2016; Yes; ---; Yes; Yes; ---; Yes; Yes; ---; Yes; Yes; ---; Yes; DOT617 M456 AS1, (E8) 43R - 003993, IR-H/A E000234 ∙∙∙∙∙∙ 6

 _L&K _; _~7W 2016; Yes; ---; Yes; ???; ---; Yes; ???; ???; ???; ???; ???; ---; ???...

 _L&K _; _40W 2015; Yes; Yes; ---; ???; ---; Yes; ???; ???; ???; ???; ???; ---; ???...

 

Good reception(Dealer's test car; Kungfugerbil;):

Package; Prod.Week; PWC; PNC; PNG; PWD; RAC; RAG; PT1; PT2; EI9; PLI; PLG; PHD; Numbers on Windsreen

 _L&K _; ~40W 2015; ???; Yes; ???; ???; ---; Yes; ---; ---; ---; ---; Yes; ???; ???...

 _L&K _; ~40W 2015; Yes; Yes; ???; ???; ---; Yes; ???; ???; ???; ???; ???; ---; ???...

[FelisBengalensis]

sorry, but any builtin navigation can't surpass online systems as Waze and Google Map

Except you have to be 'on line' to use them! If you don't have a large monthly data allowance then the built in system works just fine in the UK. I have never needed anything else. The only reason I have this Garmin in there is for traffic data, which for a DAB based system updates every 30-secs rather than every 20-30 mins as is found on UK TMC based systems.

[MartiniB]

@FelisBengalensis

"large", ha ha, 100-200Mb nowdays can't be defined that

even in abroad trips i prefer keep some local prepaid data sim

 

just try Waze, the philosophy is completely different -

online isn't only traffic data, but also accident's, roadwork's etc. reports

and even members can do online road updates by self.

friendly user interface, speed camera's warnings, fuel prices ..

 

[dstev2000]

A little update to my particular dashcam issue:

I've moved the camera up to the top of the screen, just underneath the dotted part so the camera can see out - still no GPS lock......

Even when I hold the camera right up at the top of the 'window' in the screen I get nothing. I've done a hard reset of the GPS 10 times and still diddly squat.

Out of frustration, I pulled out the carefully installed power cable so I could hold the camera outside the open driver's door. Boom: instant GPS lock!

I hard reset the GPS 10 more times whilst holding the camera outside the car and each time it locked on within 3 seconds.

It would appear I'll have to resort to plan B: a GPS re-radiating antenna. Trouble is, I don't want to stick anything on the roof which would make the car look like a wannabe minicab or whatever.

The thing is.....some GPS stuff might be ok, others might not. I would think it will all depend on the GPS chip that's used in the device in question, as well as its general design. In this case, the Thinkware F750's GPS does NOT work behind the Superb's screen. That's a kick in the balls as it was hardly cheap.

[Rifleman]

I was having problems fitting my mini806, no GPS lock.

If I just left it sitting on the dash I got a lock with no problem ( I guess enough signal through side windows reaching it ) but as soon as I stuck it to the screen below the rear view mirror there was no GPS.

I repositioned it so that the bottom edge of the base ( which has the GPS receiver ) was placed just where the black dotted area starts, to the left of the mirror console but still no joy.

Having looked closer I could see that the metal film for the heated windscreen actually extends into the dotted area by about 2 or 3 cm. I've now mounted the base just above that line and bingo! GPS now locks and stays locked.

The black dots are now just visible in the top of the picture but only cover the sky so no problem recording road.

Fitting the rear one is a bitch, 3M sticky pads refuse to stick to the black plastic cover of the high brake cluster. Will try cleaning with methylated spirit and abrade get slightly to see if that works...

[Gizmo]

Fitting the rear one is a bitch, 3M sticky pads refuse to stick to the black plastic cover of the high brake cluster. Will try cleaning with methylated spirit and abrade get slightly to see if that works...

 

I gave up after a couple of attempts and added a couple of short black screws (if you look really closely you can just see them between the brake light and rear window, if it had been really noticeable then I would have used black bolts with the bolt head on the brake light side... this would require the trim to come off again though, I had already removed this once to run the cables through the rubber sleeve between the hatch and the body)

[Rifleman]

I gave up after a couple of attempts and added a couple of short black screws (if you look really closely you can just see them between the brake light and rear window, if it had been really noticeable then I would have used black bolts with the bolt head on the brake light side... this would require the trim to come off again though, I had already removed this once to run the cables through the rubber sleeve between the hatch and the body)

I've had one last try with a sticky pad, left it overnight so the glue had chance to work. So far so good. Camera still attached and working fine. If it gives up the ghost and falls off I'll go with your suggestion and use short screws to attach something that the pad will stick to.

I hadn't spotted the void behind the black plastic, I thought the led strip would be there but now I've looked I see that it runs along the top of the housing clear of where the camera mounting goes.

Thanks for the advice Gizmo.

[MartiniB]

got useless answer from dealer:

windscreen's id code(3V0845011AENVB) is exactly same for mine and another which doesn't have problem -

lottery factor is confirmed

[Prykey]

I fixed my Inforad Safety Camera warning device to the dash board to the right of the instrument binnacle on the flat part of the dashboard top (RHD Vehicle) and it has no issues picking up the GPS signal.

 

http://www.gpsinforad.co.uk/downloads/K3_UK_Manual.pdf

[MartiniB]

@Prykey

can you please check by GPS Test

[Prykey]

@Prykey

can you please check by GPS Test

 

I do not have an Android device I'm afraid.