I've searched most of the existing threads before posting this...I had a voltage regulator failure whereby while riding the VR passed through the full AC voltage from the stator causing the following damage: burning out every bulb on the bike except for three; tachometer lights but no longer working; radio not working at all; and created a dead short that caused the 15A fuse on the accessory circuit to pop as soon as the ignition switch was turned on.

I replaced all of the bulbs that blew; replaced the VR; and then began chasing the short. After unplugging and isolating everything on the accessory circuit (speedometer, brake switches, turn signals), replacing the fuse and reconnecting one circuit or component at a time, it turned out that the voltage surge arced across two of the pins on the turn signal module and the module was creating the short.

I replaced the TSM and reassembled. Went to fire the bike up and it didn't want to start. Finally got it running and other than a low idle and the hard starting, it seemed to run fine. However, with the power restored to the speedo, the following condition showed up. The check engine light came on for the four seconds it's supposed to when the run switch is turned on and then goes out. But as soon as I push the starter button and the bike starts cranking, the light again comes on and stays on, even if I am able to get it running.

The repair manual is pointing me toward the Ignition Module, which in the parts manual for the 2000 Ultra, is indicated as Part No. 34278-99. In looking for this part (which is now considered obsolete and no longer supported by Harley) I have found this part number with the following revisions (34278-99A & 34278-99C - I have not seen a 34278-99B) my question is will these part revisions work as a replacement for the original part number?

Keep in mind that this part number is showing up as the ignition module for the FLHTCU/I EFI model...and in every reference to this part number I'm now finding, it's referring to this part number as being for a carbureted model only. Confusing to say the least. Any information I can get will be greatly appreciated.