Some electrical failures occur only while a component is moving. A connector may briefly lose contact, a solder joint may create an intermittent signal, or a communication bus may register an error for only a fraction of a second. Once the shaker stops, the component may appear to function normally again.
This is why functional monitoring during vibration testing can be an important part of automotive electrical component testing. Where monitoring is required, it provides evidence of how the component behaves under mechanical load—not only whether it still functions after the test.
The key is to define what needs to be monitored before testing begins.
An intermittent electrical failure can be very short. It may not cause visible damage and may no longer be present once the vibration exposure has stopped.
If the component is checked only before and after the test, events such as these can therefore remain undetected:
Functional monitoring during vibration testing helps capture these events when they occur. This gives the engineering team information that a conventional post-test functional check alone may not provide.
There is no single monitoring setup that fits every component. The appropriate parameters depend on the device under test, the applicable specification, its operating state, and the functions that are relevant to the test.
Typical monitoring parameters can be grouped into four areas:
Electrical behavior
Functional signals
Communication
Fault behavior
The objective is not to record every available signal. The monitoring concept should focus on the parameters needed to determine whether the component continues to perform the required functions under the specified vibration load.
Monitoring should be part of the original test plan rather than an addition made after the mechanical setup has already been defined.
Before testing begins, the test team should clarify:
The required sampling rate should also be considered in relation to the events the test is intended to detect. If a temporary interruption is shorter than the monitoring system can resolve, it may still go unnoticed.
Defining these points in advance helps ensure that anomalies are evaluated consistently during test execution.
Not every vibration test requires continuous powered operation. The applicable specification and the purpose of the test determine the required operating state.
Depending on the test program, the component may require:
For example, a control unit may need to communicate continuously during vibration so that communication interruptions or resets can be detected. Another component may be exposed unpowered and evaluated only at defined checkpoints.
The important point is that the operating state and monitoring concept match the test requirement and the intended purpose of the component.
Functional monitoring becomes particularly useful when an anomaly occurs.
Recorded data can help the engineering team determine when the event happened and connect it to the mechanical test conditions at that point. Relevant questions may include:
This creates a clearer basis for technical evaluation and failure investigation. Instead of knowing only that a component showed abnormal behavior, engineers can examine when the behavior began and under which test condition it occurred.
Mechanical and electrical data should therefore be considered together when evaluating an anomaly.
Functional monitoring may help reveal weaknesses that are difficult to identify during static evaluation or after the vibration exposure has ended.
Typical findings include:
Not every anomaly indicates the same type of failure. The monitoring data should be evaluated together with the vibration conditions, component setup, operating state, and any physical findings from the test.
A vibration test can provide more than evidence that a component remained physically intact. Where required, it can also show whether the component continued to perform its intended functions under the specified mechanical load.
In automotive electrical component testing, the mechanical setup and functional monitoring strategy therefore need to be planned together. The test plan should define operating modes, critical signals, communication interfaces, limits, interruption criteria, and reporting requirements.
At imat, we consider these factors together to develop a test matrix and monitoring concept that fit the component and its test requirements.
Planning more than the monitoring setup?
Explore how imat supports automotive electrical component testing, from vibration and mechanical loads to environmental validation and functional testing.
Effective functional monitoring during vibration testing starts with a clear question: Which functions and parameters need to remain stable—or need to be observed—while the component is exposed to mechanical load?
From there, the monitoring strategy can be defined around the component, applicable requirements, operating state, critical signals, and relevant interruption criteria.
Planning these elements before the test makes it easier to detect intermittent failures, evaluate anomalies, and connect functional behavior with the actual vibration conditions.
Discuss your functional monitoring requirements:
Planning functional monitoring for an upcoming vibration test? imat can review the component requirements, operating modes, critical signals, communication interfaces, and interruption criteria with you and help translate them into a structured monitoring concept.
An initial discussion clarifies what needs to be monitored, addresses open questions, and helps define the appropriate next steps for your test program.
Contact imat to discuss your functional monitoring requirements.
Functional monitoring during vibration testing records selected electrical, functional, or communication parameters while a component is exposed to vibration. It can help detect temporary failures that may no longer be present after the test has stopped.
The appropriate signals depend on the component and test requirements. Typical parameters include supply voltage, current consumption, contact resistance, sensor values, inputs and outputs, CAN or LIN communication, diagnostic messages, error codes, and resets.
Not necessarily. Depending on the applicable specification and test objective, a component may be tested powered, unpowered, in different operating modes, or with functional checks performed only at defined intervals.
Some failures occur only during mechanical movement and disappear once the vibration stops. A temporary contact interruption, communication error, or reset may therefore not be detected by a post-test functional check alone.