Cars should have electronic circuit breakers instead of fuses?

DC circuit breaker fuse blade box

Electronic breakers are already utilized in certain applications in cars, and also on heavy truck body control modules. But for the vast majority of power distribution, standard fuses and breakers are still the rules. Fuses are simple, cheap, and effective. As long as some nimrod doesn't replace a fuse with a larger size.

For cost, reliability, size, and weight, fuses are better than circuit breakers. That’s why automakers use them.

For most on-road vehicles, a fuse block is good enough, and cheaper. The reliability of modern wiring harnesses is really good compared to older vehicle wiring harnesses.
Cohomer fuse block box
You may see a self-resetting thermal switch (sort of a crude circuit breaker) on the 12V power outlets and on the headlight circuit, but otherwise, all fuses.

it would be ridiculously expensive and bulky for very limited benefit. A modern car typically has 40–60 individual fuses. Now, look up the cost and size of a current based circuit breaker wherever you live and work out how much space and cost that would be. Of course, they could be miniaturized and the costs reduced, but there are limits.

Circuit breakers in a car are a solution in search of a problem. Fuses cost pence and are tiny. The incidents of fuses blowing is low, and generally, if they do go there is an underlying problem that needs fixing anyway.

Of course, it’s possible to reduce the number of separately fused circuits by combining them. Old cars would have very few fuses. However, in a modern car with very complex wiring, that lack of discrimination makes fault-finding a nightmare.

Circuits which have a tendency to get overloaded a lot in cars usually have circuit breaker protection, for example, electric windows & the front seats lumbar support motors are protected by circuit breakers!
Cohomer car DC circuit breaker
I think they could be useful in certain types of vehicles, especially trucks, motor homes, and vehicles that go off-road because those vehicles have a greater chance of wiring problems due to vibration and damage by rocks.

Keep in mind that whether it's a blown fuse or an electronically disabled circuit, the circuit fault still needs to be located and repaired. What I've seen happen often in applications with electronic fault detection is the needless replacement of control modules. Folks don't understand that the module is deliberately disabling the circuit due to a detected fault.

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