Thermador PRG486GDUS - Oven/Range - Range Ignitor

[Kevin1980]

Due to intermittent range ignition I have recently replaced the simmer controller (SQ05) as well as the spark re-ignitor on my 6 burner 1/3 2/3 range/oven made by Thermador.  The range/oven model number is PRG486GDUS.  The old spark re-ignitor was part 9902 204 20284 or 5060001712, but that part is no longer available.  I was told I needed to use a new spark Re-Ignitor, part #83.22000.016 or Model RI306 made by DEFENDI.  I needed to wire it directly since the old wire harness did not fit.  

Unfortunately, I can not get the ignitors to spark now.  I do get 120V on the front end of the re-ignitor on the appropriate switch terminal when the knob is turned on.  But, I only get about 15V at the other end.  So when I test the ignitor it is energizing when the knob is turned, but, only with 15V.

My question is : How many volts are required to spark the ignitor?  If it should be more than 15V (which I assume it is), then why would I not get a higher rating as it goes through the re-ignitor?

I have not been able to get a qualified repair tech to asses the problem and fix it.  Honestly it feels like I am a bit ahead of them on the issue.....

Any help would be appreciated.