SRS Control Module Failure

As discussed further below, and by letter dated January 22, 2016, Honda is recalling certain model year (MY) 2008 through 2010 Honda Accords to replace a defective air bag/SRS control module that can result in the Supplemental Restraint System (SRS) becoming fully inoperative (disabled). See NHTSA Safety Recall 16V056 at SaferCar.gov for further details. Honda's response to an agency Information Request letter indicated that the SRS module was manufactured by tier-one supplier Continental and contained a power supply ASIC manufactured by tier-two supplier Atmel. The original ASIC was susceptible to a moisture ingress issue due to inadequate ASIC passivation layer. Water ingress could result in moisture reaching the Titanium Nitride (TiN) layer in the ASIC causing corrosion and breakage of electrical circuits. The damaged ASIC then causes failures of the SRS module resulting in 1) incomplete boot-up when power is supplied to the module or 2) the inability of the module to establish either internal or external bus communications. In either case the air bag readiness indicator light on the instrument cluster is illuminated and all air bags and seat belt pretensioners are disabled. During the investigation, ODI obtained the SRS module from a complainant crash vehicle where the air bags did not deploy despite a significant frontal impact. An inspection of the module was performed at a Continental facility. The inspection confirmed that the module had the ASIC fault thus preventing the SRS module from completing the boot-up process. An attempt was made to recover stored EDR data from the module however none was present; this outcome is consistent with an Atmel ASIC failure. A second SRS module alleged to have the ASIC problem was inspected during the same visit. This second module was unable to communicate with the test equipment. The ASIC was replaced on this module and full function was restored to the module confirming the ASIC as the cause of the SRS module fault. Acc