Thermador burner not working after potentiometer/simmer controller replacement

Hi,

My XLO burner stopped working (ignition sparks just fine, but no gas) on my Thermador SGCS304RS-XLO cooktop. I ordered the replacement potentiometer/simmer controller kit and replaced all the old components. However, the right from burner still does not work! Any suggestions on how I can troubleshoot this?

Thanks!

-Ron