If that pedal accelerates tin whiskers, you may retard the growth by using the brake pedal. American logic. /Inge PS. I'm afraid I just trigged Dewey. Let's see if he can resist. 2011/10/2 Bob Landman <[log in to unmask]> > Some of us here attended the 5th CALCE international symposium on tin > whiskers http://www.calce.umd.edu/symposiums/ISTW2011.htm where one of my > former professors, Dr. Henning Leidecker, talked about the tin whiskers he > and the others at NASA Goddard discovered in Toyota Camry accelerator > pedals. > ===================================== > CALCE Prediction of Potential Failures Risks in Toyota Vehicles Confirmed > by NASA Scientists > Investigations of Toyota vehicles have revealed tin whiskers in a critical > component of their vehicle engine control system. At the September CALCE > Conference on Tin Whiskers, Henning Leidecker and his team at NASA's > Goddard Space Flight Center, who are recognized experts on electronic > device failure and tin whiskers, presented their studies of tin whiskers on > Toyota vehicles. They determined that the risk of failure due to tin > whisker shorting in affected Toyota vehicles can be on the order of 50 to > 150 per million. This figure agrees with the number reported in a recently > published scientific journal article [Sood et al.] written by CALCE > researchers Bhanu Sood, Michael Osterman, and Michael Pecht. They assessed > the probability of a tin whisker-induced electrical short to be 140 per 1 > million, based on whisker growth statistics. > Tin whiskers are known to grow from tin-finished surfaces and have been > associated with costly failures of electronic systems. Linking tin whiskers > to electronic product failure is often extremely difficult. Tin whiskers > that bridge across terminations can create electrically resistive pathways. > And since whiskers shift under an electrostatic field and can melt when the > electrical current is drawn, they cause intermittent electrical behavior in > systems. > Figure 1 Tin whiskers on the edge of an acceleration position sensor board > connection terminal in a 2002 Toyota Camry. > > http://www.autosafety.org/sites/default/files/imce_staff_uploads/whisker%20news%20article-update-review%20%282%29.pdf > Considering the number of vehicles on the road, the presence of tin > whiskers in engine control components presents a significant safety hazard. > For this reason, best practices for electronics design stipulate that tin > not be used as a plating material. It is very questionable why the National > Highway Traffic Safety Administration--with its stated mission to --save > lives, prevent injuries and reduce economic costs due to road traffic > crashes, through education, research, safety standards, and enforcement > activity||--has not come out with a requirement that no electronics use pure > tin as a material component, since the potential for tin whiskers presents > an unreasonable and unnecessary risk. > B. Sood, M. Osterman and M. Pecht, Tin Whisker Analysis of Toyota's > Electronic Throttle Controls, Circuit World, Vol. 37, No. 3, 2011, pp. 4-9 > ===================================================== > > (One of my colleagues, Dr. Gordon Davy, presented a talk on our process: > "Whisker-Impenetrable Metal Cap Process for Electronic Assemblies" ) > > Bob Landman > Managing Partner > LDF Coatings, LLC. > [log in to unmask] > www.ldfcoatings.com > > ______________________________________________________________________ > This email has been scanned by the MessageLabs Email Security System. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 16.0 > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to > [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > For additional information, or contact Keach Sasamori at [log in to unmask] or > 847-615-7100 ext.2815 > ----------------------------------------------------- > ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 16.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------