The regulatation for Stop Lamp Illumination has been cited before (http://gm-volt.com/forum/showthread....858#post158858). Here is the table provided by Section 18.104.22.168 of United Nations Addendum 12-H: Regulation No. 13-H Revision 2, "Uniform provisions concerning the approval of passenger cars with regard to braking," (http://www.unece.org/fileadmin/DAM/t...gs/R13hr2e.pdf, page 22):
Electric regenerative braking systems as defined in paragraph 2.17., which produce a retarding force upon release of the accelerator control, shall generate the signal mentioned above according to the following provisions:
<= 0.7 m/s/s The signal shall not be generated
> 0.7 m/s/s and <= 1.3 m/s/s The signal may be generated
> 1.3 m/s/s The signal shall be generated
In all cases the signal shall be de-activated at the latest when the deceleration has fallen below 0.7 m/s/s.