See “2018-03-29 LTB01176 Technical Bulletin Water Ingress Through the A Pillar - Upper Area” and my own post re this issue on Disco Sport Forums UK with photos.
This ongoing water ingress may have caused existing but not yet developed or manifest damage, or damage that is existing but hidden. Damage that could have both structural (rust) and electrical (corrosion) implications that present serious safety, financial, and operational consequences
Structural Implications (Rust) Water has infiltrated the A-pillar area of the vehicle where it has become trapped, leaking into the passenger compartment. This could have led to the formation of rust on the vehicle’s structural components. Rust weakens the metal and compromises the integrity of the A-pillars, which can have several negative consequences:
Safety Concerns: The A-pillars provide crucial structural support to the vehicle’s roof and play a role in maintaining the structural integrity of the passenger compartment during collisions. Rust-induced weakening can compromise this support and increase the risk of injuries in the event of an accident.
Weakening of Structural Components: As rust progresses, it can cause metal parts to weaken, leading to the potential collapse of structural components like the A-pillars. This can affect the overall crash safety of the vehicle, as the A-pillars play a role in maintaining the structural integrity of the passenger compartment during an impact.
Longevity: Rust can spread over time, potentially affecting nearby components as well. If left unchecked, it can significantly reduce the overall lifespan of the vehicle due to accelerated corrosion and structural degradation.
Resale Value: Vehicles with evidence of water ingress will have lower resale value, as potential buyers will be wary of investing in a car with compromised safety and structural integrity.
Electrical Implications (Corrosion) Water ingress into the A-pillars may impact the vehicle’s electrical systems, leading to corrosion and malfunctioning of various electrical components:
Corroded Wiring and Connectors: Water may be seeping into the wiring harnesses located within the A-pillar area and could have led to corrosion of electrical wires, connectors, and components. Corroded wiring could disrupt electrical circuits, leading to malfunctioning of various vehicle systems such as power windows and mirrors, airbags, and the vehicle’s engine control unit.
Electronic Components: Modern vehicles have a variety of electronic modules and sensors located in the A-pillar area. Corrosion caused by water ingress can damage these components, resulting in faulty systems like airbag deployment, lighting, or the infotainment system.
Fire Hazard: Water intrusion into the electrical systems could cause short circuits, leading to overheating and potentially result in electrical fires or other safety hazards.
Increased Repair Costs: Diagnosing and repairing electrical issues caused by the water ingress will be complex and time-consuming, leading to high future repair costs.
Comments To mitigate water ingress implications, manufacturers design vehicles with water management systems, seals, and drainage pathways to prevent water from entering critical areas like the A-pillar. Once water ingress is suspected, it is crucial to address the issue promptly by an authorized service centre to assess and repair any damage before it worsens.
Overall, both structural and electrical damage resulting from water ingress through the upper A-pillar area of the vehicle could have serious safety, financial, and operational consequences, underscoring the importance of addressing such issues as soon as they were detected per JLR Technical Bulletin LTB01176 ‘Water Ingress Through The A-pillar - Upper Area’ was published.