ECU issues and how to fix them The ECU is truly a wonderful piece of engineering. Not only does it contain a lot of functionality, but to reliably operate in a harsh environment with very variable conditions is a big achievement. However, the reliability still leaves something to be desired every now and then. Why can’t they solve these weaknesses?
by active components) dissipate quickly. Deformation and vibration therefore occur way less with ceramic printed circuit boards. It also prevents possible consequential damage due to these deformities. Cracks in solid connections are therefore also relatively rare. So, all-in-all, the use of ceramic material really has huge advantages. We even dare to say that the now somewhat older green printed circuit board is partly to blame for the varying reliability of some current ECUs.
It might be useful to start with some elaboration about the technology that’s used inside an ECU. Of course, the basis is formed by a processor, memory and a PCB (Printed Circuit Board), but there is really much more to tell.
Components on, and inside, the PCB
AUTOTECH
The PCB
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We’ll start with the PCB itself: The well-known green printed circuit board, made out of fibreglass and epoxy resin, is still used regularly, but the arrival of ceramic material has made some manufacturers switch. Ceramic printed circuit boards can conduct and dissipate heat much better and are made of much finer and better structured material, which allows for very high precision manufacturing. This also has its advantages for printed circuit board design, as it also makes possible very small and complicated 3D structures. Car manufacturers are very eager to take advantage of these characteristics, as any form of space and weight saving is welcomed with open arms. We therefore expect to see the use of ceramic material in ECUs even more in the near future. Ceramic printed circuit boards are mostly glued to an aluminium base plate with a heat-conducting paste. This gives the circuit board its firmness and lets the heat (generated
It should come as no surprise that this difference in printed circuit boards also results in a different use of components. A conventional printed circuit board has a coarser structure in comparison to the ceramic variant. The components themselves are therefore logically somewhat more "robust" in design. Most contact points are therefore large enough to be seen without a microscope. You would therefore think that these components are also more reliable than the smaller fragile components on a ceramic printed circuit board, but strangely enough, this theory does not seem to hold true in reality. The larger components still regularly fail. Could low manufacturing costs play a role in this? Fortunately, with suitable (solder) equipment and sufficient skill, much is possible in repairing connections and replacing components on these conventional printed circuit boards, even if the contact points are located beneath the component, as is the case with processors such as BGAs. You’ll need special high-end equipment that can heat locally with extreme precision, but it’s doable for real experts. So, if something fails on a conventional printed circuit board, repair is possible in many cases. However, with components that are used on a ceramic printed circuit board, it suddenly
