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What is reliability testing?

In recent years, with the transition to mobile and digital control, electronic devices are now used in a variety of environments. Products are required to be durable in harsh environments, and it is important to check the reliability of products in many areas to prevent problems in the market, in order to meet the quality required by customers.

Reliability testing of in-vehicle equipment

Reliability for automotive components has been considered from various viewpoints from the extent of the vehicle’s mobility and the area of use. With the recent shift to electrification, the number of electronic devices in automobiles is increased, and electronic devices are now required to be durable enough to withstand the harshness even in places such as engine rooms that are subject to severe vibration, high temperatures and exposure to oil and salt water. In order to evaluate the reliability of automotive components and detect potential defects or vulnerabilities, we perform environmental tests such as temperature, humidity, atmospheric pressure, vibration, shock, waterproofing, dust, and salt, as well durability tests against stresses such as temperature differences, vibrations, and electric voltage surges.

In addition to testing services based on standards, UL is able to provide our testing sites and equipment, customized tests and measurements, and advisory for test items. We also support a wide range of reliability tests except for in-vehicle equipment. To learn more, please contact us.


Humidity and temperature test/Temperature and humidity cycle test

By repeatedly changing the temperature and humidity, this testing service evaluates reliability and durability of the changes. We perform temperature and humidity cycle test (heat cycle test) using temperature and humidity chamber. The chamber adjusts the temperature and humidity, to perform environmental and reliability tests under various temperature and humidity environments. Customized tests, and tests with powered-up and operating are also available.

Equipment: High-power high-temperature thermostat, large thermostatic chamber Standards:
LV124/ISO 16750-4/ISO 19453-4/JASO D 014-4/IEC 60068

Thermal shock test

In thermal shock test, UL evaluates products’ resistance to sudden change of temperature, by exposing products to high temperature and low temperature alternately in a short time. It is also known as thermal cycle testing. Repeated rapid temperature changes cause the test material to expand and contract. Materials with different coefficients of expansion produce stresses due to differences in the rate of expansion, which can cause cracks and fractures when such is repeated. In addition to damper type thermal equipment, this service features an elevator type thermal shock equipment that is used for testing for Europe with high capacity and is faster to reach the set temperature, allowing us to support more demanding environmental tests.

Equipment: High-capacity elevator type thermal shock equipment, thermal shock equipment (damper type), humidity thermal shock equipment (damper type) Standards:
LV124/ISO 16750-4/ISO 19453-4/JASO D 014-4/IEC 60068

Splash Water Test (Ice Water Shock Test)

UL simulates the thermal shock caused by cold water splashing when a vehicle travels on a wet road in winter. For electronic systems and components installed exterior of automotive, we test the impact of thermal shock on both products’ mechanical strength and waterproof performance. In this service, we provide splash water test that apply cold water from 0 to 4 degrees Celsius to the product, and submersion tests that submerge the product in cold water while keeping in operation. We are also able to customize water temperature, depth of water, and liquid type.

Equipment: Splash water Testing equipment Standards:
ISO 16750/JASO D 014-4/Automobile Manufacturer Standards

International Protection (IP) test

For electrical and electronic products, we evaluate water resistance and waterproofing when subjected to outdoor wind, rain, and water splashing, etc. For automotive components, we provide testing service to evaluate waterproofing, water resistance, drainage, and changes in functionality. This service enables water-resistant testing corresponding to IP code. UL is also able to support cycle tests using a thermostatic bath and tests during power-up and while in operation.

Equipment: Water and rain resistance tester (see video for details) Standards:
LV124/IP code (IPX1, X2, X3, X5, X4K, X5, X6, X6K, X7, X8, X9K)/IEC 60529/ISO 20653/JIS D 0203


By integrating the expertise of safety standards, testing ability for safety certification, and the experience of EMC services for automotive components over 15 years, UL offers the reliability testing services for automotive components.

● On Stop Service – Comprehensive testing menu for automotive components: Reliability, EMC, Wireless, etc.
● Wide range of Standards – International standards, Japan / Global automotive manufacturer standards
● Trusted services – Trusted testing and certification services over 100 years

High-power temperature and humidity chamber Ion migration evaluation system
Thermal shock equipment (elevator type, damper type) Digital microscope
Thermal shock equipment with humidity function (damper type) Drop tester
Vacuum oven / dryer Impact tester
Dust resistance tester (floating type, air flow type) Large thermostatic bath
Water and rain resistance tester Power supply and electric load device
Combined corrosion tester Universal material tester
Combined environmental vibration tester Highly accelerated stress test chamber (HAST CHAMBER)
Conductor resistance evaluation system

Click here for details of testing and equipment specifications (Brochure DL)