ahhh no wonder, it's an APC. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt='
'> Kidding. (sort of...)
Anyway my best understanding of "brain" would be ECU ... but plugging your tach into your ECU? Sounds kind of strange. Maybe your fuse box? ...errr... :shrug: