Cracked Windscreen, Anything I Need to Watch for??

helmik

Member
So, got a stone or something must have hit the screen sometime in the last few days, only spotted it today. I’ve arranged for Autoglass to attend on Friday but I’ve heard various horror stories so just a question really as to whether there’s anything I need to watch out for or check after he’s been please?
Ta
Mick.
 
helmik said:
So, got a stone or something must have hit the screen sometime in the last few days, only spotted it today. I’ve arranged for Autoglass to attend on Friday but I’ve heard various horror stories so just a question really as to whether there’s anything I need to watch out for or check after he’s been please?
Ta
Mick.

I’ve read reports of the glass on replacement screens being flexible when pressed, I also there’s a sensor for the auto wipers that’s bonded to the glass so make sure that they work ok, you could take some photos of the screen position and trims to compare after it’s been changed to make sure everything fits as it should.
 
Sorry to hear of that OP. :(

This thread may be worth a quick read though:- https://z4-forum.com/forum/viewtopic.php?f=3&t=123428&hilit=windscreen
 
If you have iDrive then there is a GPS aerial to worry about..many fitters break that as well…

You need a fitter whose done a similar BMW windscreen.

The rain sensor needs re-calibration when re-fitted..

I was lucky the area manager elected to do mine as he had so many dissatisfied customers from subordinates who has screwed the install up..
 
Cheers guys, I will do some pics in the morning, I’m off to the Triumph factory later on so I can do them first thing, new screens being done Friday after a 45 mile drive!! See how it copes with that.
Not too concerned about the seal, if it’s wrong they will keep getting called back until it’s sorted.
There is a sensor in the screen so I will check everything works afterwards. I assume it’s just for rain, nothing else is there??
Ta
Mick
 
Sorry PBondar, posted before I read your reply. The GPS aerial, is that In The centre bit where the rain sensor lives??
How does the rain sensor get calibrated!
Mick
 
helmik said:
Sorry PBondar, posted before I read your reply. The GPS aerial, is that In The centre bit where the rain sensor lives??
How does the rain sensor get calibrated!
Mick

Yes it it ..can be damaged very easily..you need a s/w tool to recalibrate it..the company should have the tool and know how to do it :thumbsup:
 
My first autoglass windshield cracked after a few days. Replacement fitter said it could be where the mastic was started from, he said he starts at centre. I noticed how they were stored on racks, i said it could been dropped on the rack. The crack started from where a rack support would have contacted.
 
So, all done today. The screen looks exactly like the one that was replaced. Not sure if that means it’s been done before or not. Near the top right hand corner there’s an arrow pointing down, with a line and I think the letter A, so is that on a genuine BMW screen as it was on the previous screen. Just wondered.
All looks ok, he told me he had checked the rain sensor, he also spent some time cleaning off some bond that was visible.
Fingers crossed it will be fine but we are off to London tomorrow in the TT so it won’t get a real run until I go home on Tuesday.
Cheers, have a good, hot, hot hot weekend all.
Mick
 
As I thought, guessing that mine may not have been the original screen, or else Autoglass have done a brilliant job of getting a very good copy of the BMW version.
Mick
 
Bit more, the screen has a manufacturer’s name on it of FUYAO, laminated, solar tint. As I think this is the same as the original, I can only guess that maybe my screen has been replaced in the past, unless someone with a 2016 2.0 can check this to see if these are originals maybe??
Mick.
 
Pbondar said:
The rain sensor needs re-calibration when re-fitted..

Any idea if that applies to the E86 as well?
Might get mine replaced but if its going to be a total palaver I might pass :rofl:
 
Flyingfifer said:
Pbondar said:
The rain sensor needs re-calibration when re-fitted..

Any idea if that applies to the E86 as well?
Might get mine replaced but if its going to be a total palaver I might pass :rofl:


It does need to be reset..you can pray that it works out of the box..otherwise some very modest coding required..the supplier/fitter should be able to code it..

TIS refers to the E86 here..

Rain/driving lights sensor (RLS)
The rain-driving light sensor has integrated sensors that sense the wetness on the windscreen glass and the ambient light.
Rain sensor
The rain sensor is an optical system. It consists of an optical element bonded on the windscreen and an electronic element. The electronic evaluation unit and 4 optical transmitter and receiver diodes are integrated in the electronic element.
Function
The rain sensor is activated when the wiper switch is moved to the first stop position.

When the rain sensor is activated, visual feedback is given to the driver in that one wiping cycle is executed first. Then, the transmitter diodes emit an infrared light which is guided across the optical element to the windscreen. If the windscreen is completely dry and clean, the infrared light is fully reflected to the receiver diodes.

If there is water or dirt in the area of the optical element on the windscreen, full reflection of the infrared light is no longer possible. Part of the light penetrates the windscreen so that only part of the light arrives at the receiver diodes. The electronic circuitry detects how much water is on the windscreen on the basis of the amount of light that is being blocked out and send a signal to that effect via the K bus. The ZKE basic module then performs a wipe cycle. In the case of very heavy rain, the intermittent operation goes into stage 1 or stage 2 of the continuous wiping mode.

A heating element integrated in the rain sensor prevents misting of the optical element or the diodes.

The sensitivity of the rain sensor can be varied in 4 sensitivity stages by means of the knurled wheel on the wiper/washer switch. Each time the adjuster wheel is moved in the ”Increase sensitivity” direction (upwards), a wipe cycle is carried out.

When the vehicle is at a standstill, there is an automatic reduction of the sensitivity so that the wiper usually runs in intermittent mode.

If the rain sensor fails, the wiper runs at a fixed time interval.

For safety reasons, the rain sensor is switched off when terminal R is switched off.

Requirements for faultless operation of the rain sensor are:

No wax smear on the windscreen
Wiper blades OK
Windscreen glass free of faults in the area of the rain sensor
Optical element bonded free of bubbles with the windscreen glass
Initialisation
Due to the optical process, the rain sensor has to be adapted to the windscreen. This adaptation takes place at initialisation.

Requirement for faultless initialisation is that the windscreen glass is dry, clean and free of defects in the area of the rain sensor.

The initialisation is performed using the service function ”Initialise rain sensor” in the BMW diagnosis system. In the service function, the adaptation values in the rain sensor are deleted. This is followed by adjustment of the sensor system to the windscreen based on the following sequence:

Switching off the rain sensor
Switch off terminal 15 and terminal R
Switch on terminal R and terminal 15 and wait 10 seconds
In the 10 seconds waiting period, the new adaptation values are determined and stored.

Initialisation of the rain sensor is necessary:

After replacing the windscreen
Fitting a used rain-driving light sensor

Note: a used sensor must be coded beforehand!

Driving light sensor
The driving light sensor consists of two photodiodes and an electronic evaluation unit. The photodiodes are arranged in such a way that both light striking the sensor from the front and light striking the sensor from above (ambient light) are sensed.

If there is a change in the light conditions, a signal is sent across the K bus. If the automatic headlights system is active, the light control centre switches the headlights on or off.

The light sensing is active as of terminal R, independent of whether the automatic driving light system is switched on or off.

Adjustment of the driving light sensor on the windscreen is by means of coding. This is why a used sensor must be recoded on installation!
 
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