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
>
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