Automotive Parts Industry Testing Case

Poor battery sealing may allow moisture or dust to enter the battery, causing insulation degradation, internal short circuits, and in severe cases, fire or explosion.

Electrolyte leakage can corrode electrodes and connectors, reducing battery capacity and charge/discharge efficiency, significantly shortening driving range.

Battery housings should meet at least IP67 standards to ensure stable operation in rain, humidity, or dusty environments.

Battery packs need to undergo pressure and vacuum testing during design and inspection to ensure no leakage under external pressure.

Moisture Ingress: Rain, mud, or car wash water can enter the engine bay through poorly sealed areas, causing electronic components to get damp, corrode, or short-circuit.

Headlight Performance Impact: The intake system drawing in water or dust-laden air can severely affect engine life and efficiency.

Reduced User Satisfaction: Seal defects may cause increased wind noise, heat escape, and unpleasant odors inside the cabin, impacting user experience.

Impact on Overall NVH and Protection Level: For premium vehicles, the engine cover’s sealing integrity directly affects vehicle certification levels (e.g., IP rating, NVH, thermal simulation verification).

Prevents water ingress short circuits: In rainy driving or high-pressure washing, poor sealing can cause water ingress leading to short circuits and damage.

Ensures insulation safety: Moisture intrusion can cause circuit board breakdown and failure, affecting the vehicle’s charging system.

Meets protection rating requirements: Most on-board chargers must pass leak tests to meet IP67/IP68 ratings.

Improves overall vehicle quality and reliability: Sealing issues are a key reason for high after-sales maintenance rates and customer complaints.

Moisture ingress: Rainwater, dust, and wash water can enter the engine bay through poor seals, causing electronic component dampness, corrosion, and short circuits.

Engine performance degradation: Intake of water or dust-laden air seriously affects engine life and efficiency.

Reduced user satisfaction: Seal defects can increase wind noise, heat leakage, and odors inside the cabin.

Affects overall vehicle NVH and protection ratings: Especially for high-end models, the sealing integrity of the engine hood directly impacts vehicle certification (e.g., IP ratings, NVH, thermal simulation validation).

Lens fogging and blurred images: Affect autonomous driving and assistance functions.

Water ingress causes electronic component short circuits: Module failure and system errors.

Sensor false alarms or non-responsiveness: Safety risks.

Fails to meet IP67/IP69K protection certifications: Cannot be shipped or is returned by customers.

Pressure Decay Method: Inflate the light housing, then check if internal pressure decreases; low cost and fast testing speed; suitable for small, regularly shaped reverse light assemblies.

Mass Flow Method: Use mass flow sensors to detect internal leakage flow of the taillight; accurate data and high stability, supports automated testing; suitable for high-precision or LED control circuit reverse lights.

Helium Leak Detection (optional): Used in R&D or high-end vehicle testing for micro-leak detection; higher cost and generally used during validation phases.

The transmission is filled with oil that lubricates gears, bearings, and other moving components. If the housing has undetected micro leaks, it can lead to overheating, component damage, or even seizing of the transmission.

When the transmission housing lacks sufficient leak, external moisture, rainwater, or car wash water may seep inside, causing the lubricant to emulsify, reducing performance, and leading to corrosion of internal gears and bearings.

As modern automotive manufacturing standards continue to rise, component precision must also improve to meet overall performance requirements. The transmission housing must therefore meet specified leak standards.

For OEMs and suppliers, neglecting leak testing may result in oil leakage issues after delivery, product recalls, increased after-sales complaints, and damage to brand reputation.