A 1999 CL didn't come with HIDs from the factory. It was some sort of added aftermarket system.
There's only 3 parts in the system, the ballast, the igniter, and the bulb. If it's not the ballast or the bulb, it must be the igniter. If all three are good, you're not getting power to the headlight. Are you getting 12V to the ballast?
Tim Poliniak - ASE Certified Parts Specialist, 21 years with Acura/Honda
Acura of Peoria ~ www.oemacuraparts.com