there is , i just did this 2 days ago
its in the r32 gtr manual, i have on cd, i supose you can get a pdf somwhere on the net.
cant remmeber the page,
if you can wait till tomroow, i will tell you the page.
you have to read the voltage coming out of the 1 o 120 degree pin , wich is pin 1 and 2 looking at the conector off the cas, its the 1rts and second from the left.