The recent adoption of the ISO26262 Functional Safety Standard has lead to the need for a greater degree of rigor in the technical, organizational and process aspects of electronic ECU engineering. One new facet of this standard also covers (in part 9.7) the analysis of dependent failures at manufacturing time, not only the microcontroller, but also for the plethora of connected system ASICs, input circuits, output drivers and communication devices in the PCB of the ECU. This paper will describe the CAN based end of line ECU self test system that was implemented at a major tier 1 supplier to address the issues of efficiently gaining a high degree of diagnostic coverage of single point faults and latent faults in highly integrated automotive ECUs. It will outline the requirements and demonstrate how a flexible system solution allows not only efficient test of the new design but also addresses the degree of rigor required to be demonstrated when testing a production volume ECU to ISO26262 functional safety standard.
