(ET) Intermittent 3rd speed on E12

[Richard Zachary <postmaster njcfsa org>]

Most of the time, I can't get the 3rd speed to work on my E12.  Have 
done some testing but if its a bad connection, I have not been able to 
find it. With help, have temporarily put in a bypass circuit with spare 
contactor in parallel with contactor 2A over to wire #25 that gets me 
from 2nd to third speed and holds it (after hitting the power pulse 
switch). In studying ET literature, I found a flow chart that says to 
check diode CR12 on the Varistor assembly.  I re-soldered the ends to 
the Varistor board but no change. Would like to replace this CR12 
diode.  I know very little about this type of thing and went to Radio 
Shack but they knew nothing. Can anyone help in identifying this diode 
for me so that I can locate and buy a new one?
Thanks in advance,
Richard "Zack" Zachary