DIAGNOSIS A new grinding noise after an impact is a classic sign of damaged gears in the transmission. You likely cracked a tooth on one of the nylon or metal planetary gears inside the gearbox.
FIX Stop using it immediately to prevent further damage. You'll need to open the drill's housing to inspect the gear assembly. On the P215, the two-speed planetary gearbox is a self-contained module. Look for obvious broken teeth, metal shavings, or misaligned gears.
IF THAT DIDN'T WORK If the gears look okay, the bearing that supports the motor shaft or the chuck might have been knocked out of alignment, causing the grinding. This is trickier to diagnose and fix, often requiring full gearbox replacement.
HEADS UP Running a drill with damaged gears will quickly destroy the rest of the gearset and can seize up entirely. The repair is often a cost-benefit decision—a new gear kit versus a new drill. If you're not comfortable taking it apart, this is a job for a repair shop.