Windscreen
The windscreen is far more than just a viewing window – it is a central safety component of your vehicle. As a load-bearing element of the body, it performs protective functions in accidents, serves as a carrier for driver assistance systems and influences the stability of the entire vehicle. In this comprehensive guide you will learn everything worth knowing about the windscreen: from construction and function to repair and replacement, as well as costs, insurance questions and the interaction with modern vehicle electronics. Electronicx GmbH from Cleebronn supports you with technical expertise and suitable components for your vehicle.
Construction and function of the windscreen
Modern windscreens are made of laminated safety glass (LSG). Two layers of glass are bonded together by a highly elastic, tear-resistant plastic film made of polyvinyl butyral (PVB). This construction ensures that the windscreen does not shatter into sharp-edged fragments in the event of a stone chip or accident. Instead, fragments adhere to the film, which massively reduces the risk of injury to occupants.
Why is the windscreen a safety component?
The windscreen contributes significantly to the rigidity of the passenger cell. In particular, in the event of a rollover, it prevents the roof from buckling and protects the occupants. It also serves as a fixed base for airbags: the passenger airbag braces against the windscreen when it deploys. A windscreen that has been installed improperly or is damaged can therefore impair the function of restraint systems. For this reason, every replacement must be carried out in accordance with strict manufacturer specifications and using suitable adhesives.
Legal requirements and inspection criteria
The Road Traffic Licensing Regulations (StVZO) stipulate that the driver's view must not be impaired. Damage in the direct field of vision – roughly the area swept by the windscreen wiper – generally leads to failure during the main inspection (HU). Cracks longer than 10 cm or extending to the edge of the windscreen are also considered a significant defect. An intact windscreen is therefore not just a comfort feature but a requirement.
Stone chip or crack: repair instead of replacement?
Not every stone chip requires a new windscreen. Small, clearly defined damage can often be repaired cost-effectively and in a short time. The size, location, type and age of the damage are decisive. A repair is generally possible if:
- The stone chip has a diameter of no more than 2–3 cm (depending on the manufacturer's specification).
- The damage is not in the driver's direct field of vision.
- No crack longer than 5 cm extends from the point of impact.
- The outer glass layer is damaged, but the inner layer remains intact.
- The damage is no more than a few days old and no moisture has penetrated.
Typical damage patterns and their assessment
A simple stone chip without crack propagation can usually be repaired within 30–45 minutes. A special synthetic resin is injected into the break under vacuum and cured with UV light. The result is visually almost invisible and restores the strength to approximately 80–90%. In the case of cracks longer than 5 cm, located in the field of vision or extending into the PVB interlayer, replacement is unavoidable. Damage in the area of sensors, cameras or heating wires can also rule out a repair, as the function of electronic systems could be at risk.
Replacing the windscreen: procedure, costs and special considerations
Replacing a windscreen takes about 1.5 to 3 hours in a specialist workshop. In addition, the adhesive must cure before the vehicle can be fully loaded again – usually 6 to 12 hours. Installation is carried out in accordance with manufacturer specifications using special polyurethane adhesives that ensure a durable and sealed bond. Mobile windscreen services also carry out the replacement on site, provided the ambient conditions (temperature, dryness) are suitable.
Cost factors at a glance
The cost of a new windscreen varies greatly depending on the vehicle model, equipment and manufacturer. Whether original parts (OEM) or aftermarket parts are used is also decisive.
| Vehicle class / equipment | Special considerations |
|---|---|
| Small car (e.g. VW Polo, Opel Corsa) – basic windscreen | Without rain sensor, no calibration required |
| Compact/mid-range with rain sensor | Sensor may need to be reattached |
| Upper class / SUV with camera & HUD | Calibration of driver assistance systems required |
| Premium with heated front windscreen | Electrical connections, often OEM required |
Calibration of driver assistance systems (ADAS)
Modern vehicles have cameras, lidar or radar sensors behind the windscreen. These systems – such as lane keeping assist, traffic sign recognition or emergency brake assist – rely on a precisely positioned and faultless windscreen. After a replacement, the sensors generally need to be recalibrated. Special target boards and diagnostic devices are required for this.
Windscreen and vehicle electronics: what you need to know
Today, the windscreen is a highly integrated component that is connected to numerous electronic systems. These include:
- Rain sensor: Detects moisture on the windscreen and automatically controls the windscreen wipers.
- Light sensor: Measures the ambient brightness and switches the dipped headlights on/off.
- Camera for driver assistance: Detects road markings, traffic signs and obstacles.
- Head-up display (HUD): Projects information onto the windscreen – special coatings prevent double images.
- Heated windscreen: Fine heating wires or a conductive silver coating ensure rapid defrosting in winter.
The utmost care is required when replacing such a windscreen. Incorrectly positioned sensors or damaged heating wires lead to malfunctions. The replacement should therefore only be carried out by trained personnel with the appropriate equipment.
Connection with TPMS / tyre pressure monitoring sensors
Even though the windscreen itself does not contain any tyre pressure sensors, there are indirect connections: many vehicles use the data from the wheel speed sensors (indirect TPMS) to detect pressure loss. These sensors are located on the wheel hubs and are evaluated by the control unit. Replacing the windscreen has no direct influence on this. Nevertheless, it is worth checking the condition of the TPMS sensors during a workshop appointment – especially if the vehicle is already older. Further information on the design, function and replacement of tyre pressure monitoring systems can be found in our detailed guides: Tire Pressure Monitoring System Sensors and Sensores TPMS. There we also explain how to recognise defective sensors and what costs are incurred when replacing them.
Law and insurance: who covers the costs?
In Germany, partial comprehensive insurance generally covers the cost of repairing or replacing a damaged windscreen – provided the damage was caused by stone chips, hail or other insured events. Many insurers waive the excess for a pure repair in order to avoid a more expensive replacement. Before commissioning work, you should always consult your insurer and clarify which workshops are accepted and which documents need to be submitted.
An important note: even if the insurance covers the damage, you should pay attention to quality. Where possible, use windscreens with an E-mark and manufacturer approval. Improper repair can cause subsequent damage that is then no longer covered by the insurance.
Buy a windscreen online or have it fitted by a specialist?
On the internet you will find a large selection of windscreens at prices that are sometimes significantly cheaper than in a workshop. But beware: fitting is demanding and requires special tools, adhesives and experience. Mistakes during fitting can lead to leaks, corrosion or even the windscreen popping out in an accident. In addition, improper fitting not only invalidates the vehicle's approval but also poses safety risks. If you buy the windscreen yourself, you should commission a certified specialist to fit it. Clarify in advance whether the business accepts third-party material and what liability is assumed.
Electronicx GmbH is your partner for vehicle electronics and accessories. Even though we do not sell windscreens, we support you with the necessary accessories for your vehicle's electrics – such as batteries, chargers or TPMS sensors. These reliably supply 12 V on-board voltage and are available in capacities from 60 Ah to 95 Ah and cold cranking currents from 640 A to 850 A (CCA). Models with 70 Ah and 760 A CCA for mid-range vehicles are particularly popular. An EFB battery typically achieves 200–300 cycles at 50 % depth of discharge, while AGM batteries often manage 400–600 cycles. Our location in Cleebronn, Baden-Württemberg, delivers quickly throughout the Federal Republic.
This is how you combine the repair of your windscreen directly with a new battery or new sensors – all from a single source.
Frequently asked questions about the windscreen
Can I keep driving with a stone chip?
A small stone chip without cracking generally poses no immediate safety risk if it is outside the field of vision. However, you should have the damage repaired promptly, as penetrating moisture and temperature fluctuations can enlarge the crack. On longer journeys or with strong vibrations, the damage can spread – a repair is then often no longer possible.
How long does replacing a windscreen take?
The actual replacement takes about 1.5 to 3 hours in a specialist workshop. Afterwards the adhesive must cure: depending on the product and temperature, the vehicle can be used safely again after 6 to 12 hours. For vehicles with driver assistance systems, additional time is required for calibration (approx. 1 hour).
Does the insurance cover the repair?
Yes, as a rule the partial comprehensive insurance covers the repair or replacement of a damaged windscreen. However, you usually have to pay a contractually agreed excess. For a pure repair, many insurers waive the excess. Clarify in advance with your insurer which workshop you may choose and which documents are required.
Does the driver assistance system need to be calibrated after a windscreen replacement?
Yes, if your vehicle has a camera behind the windscreen (often with lane keeping assist, traffic sign recognition or emergency braking assist). After replacement, the camera must be realigned and calibrated so that the systems work correctly.
Can I replace the windscreen myself?
Self-installation is strongly discouraged. In addition to special tools and adhesives, exact positioning and curing are crucial. Mistakes lead to leaks, corrosion or safety risks. In addition, the operating permit expires if the installation is not carried out properly. Always commission a specialist workshop.
What is the difference between repair and replacement?
In a repair, a small, isolated stone chip is filled with synthetic resin and cured. This is inexpensive and preserves the original windscreen. A replacement is necessary if the damage is too large, lies in the field of vision, the PVB film is damaged or cracks are longer than 5 cm. The replacement costs a multiple and often requires calibration.
Does the windscreen affect the function of TPMS sensors?
No, the windscreen has no direct influence on tyre pressure sensors. Indirect systems use wheel speed sensors located on the axles. Direct systems have sensors in the tyre. A windscreen replacement does not change this. However, it makes sense to have the condition of the TPMS sensors checked at the same time during a workshop appointment.
Conclusion: care and quality pay off
The windscreen is a safety-relevant component that goes far beyond mere visibility. Whether repair or replacement – quality, proper installation and correct calibration of the electronics determine safety and functionality. Find out in advance about costs, insurance and technical requirements. And if you also need a new battery or new sensors during a workshop appointment, Electronicx GmbH is your reliable partner. Contact us if you have any questions: phone +49 7135 7194106, email [email protected].
Address: Electronicx GmbH, Hindenburgstr. 37A, 74389 Cleebronn, Germany. Managing Director: Andreas Emschanow. VAT ID: DE300176428, HRB 752730 (Stuttgart Local Court).