Have a 2 lamp (FO32/835/ECO) fixture, with a Philips Advance Optanium IOP-2PSP32-N AC ballast, and a Philips Bodine B50 emergency ballast. Last week both lamps and the charging indicator light were not working. I checked for power to both ballasts, which was confirmed w/ 120V, ohmed both the high and low side of AC ballast, showed high side was open. I replaced the AC ballast which did not fix anything. changed out the emergency ballast yesterday with brand new, yet still not working. Any advice what my issue might be? Could the tombstones be the issue?