Leo Bodnar BU0836X and EFIS panel

I need some guidance on an issue I have with the VOR/ADF switches on the EFIS panel and the Leo Bodnar BU0836X card. The switches are ON-OFF-ON and mapped to the BU0836X as B17-GND-B18. I have no issues switching to VOR1 and ADF1. My issue is the OFF setting. I can't figure out how to get it to move to OFF when I move the switch to the center (OFF) position.

I used this document by Ian as a reference => http://www.737ng.co.uk/EFIS_BU0836_HOWTO.pdf


Any help would be greatly appreciated.

Thanks,
Steve