'... my' G3 B&W 'would not turn ON. It is competly blank. It's black as if it is not turned on. I can hear the CPU running, but nothing comes on the screen. I desperately need help here.' - I doubt very much that the CPU is self oscillating - and therefore producing an audible sound. It is more likely that a fan or fans is / are being heard.
With respect to repairing the G3 B&W's MacOS X 10.3.9 hard disk drive, hdd - there was no mention as to why 'Disk Warrior' was used in the first place; considering, it is used for hdd directory structure repairing and not routine or preventative means.
Assuming that the display actually works (for example - with another computer, and / or its video cable is properly connected, as well as, the AC power cord), are you able to insert and boot from the Panther installation CD - with a result of a viewable screen?, if so - 'Disk Warrior' (may have) damaged the G3's boot drive's directory tree, etc. Use 'Disk Utility' of the Panther installation CD to 'Repair Disk' and 'Repair Disk Permissions' of the G3's hdd, then attempt to boot from the G3's hdd.