Automotive functional safety ISO26262

Few days ago, we were participating in a meeting with a few colleagues and going through the Safety manual of a Software vendor who was providing us two ASIL Components, X and Y.  There were several requirements stated in this Safety manual that we had to satisfy. There was one such requirement that stated: “The Integrator shall ensure that the version number for the code of Component X and Component Y that is integrated in the System shall be compatible. These version numbers are hard coded in ROM – Required ASIL level: ASIL B”.  The Software colleague in our meeting immediately jumped in and said "Oh, this is easy, I can do a review in the Integrated SW and check that the version no of X and Y are compatible.” Later, he paused and said, “ Oh… but wait, this is an ASIL B requirement - so that means I cannot check just by a review, the SW needs to check during run time that the version numbers are compatible. If they are not compatible, it needs to trigger a safe state!" Anot...

The ISO26262 provides a bookish definition for Systematic faults and failures. In this post, we have explained our understanding of what these mean. To do so, we have described the following aspects: An easy way to understand systematic faults & systematic failures Possible scenarios in which systematic faults could occur Challenges with complete elimination of systematic failures Probability of systematic failures An easy way to understand systematic faults & systematic failures In simple terms we would like to call Systematic faults as "Method or Process faults”. It is any fault in the way of applying methods or processes whose consequent failure shows up in a deterministic way. This consequent failure is what is called a Systematic failure. What do we mean by "deterministic"? It means that if the same fault is injected into the system 'n' no of times under specific conditions, the same failure will occur every time. The failure is not really tied to th...