The symptom pattern

The drill is running normally, mid-hole or mid-screw, and it just stops. No slowing down first, no grinding, nothing on the drill to say why — pull the trigger again and sometimes it does nothing at all. It’s an alarming way for a tool to fail because there’s no lead-up to it, and on an 18V XR drill like the DCD776 it’s rarely the drill itself that’s at fault.

What’s actually happening

DeWalt builds its XR Li-Ion tools with what it calls an Electronic Protection System, and its own manual states it plainly: the system “protect[s] the battery pack against overloading, overheating or deep discharge,” and “the tool will automatically turn off if the Electronic Protection System engages.” There’s no separate warning light on the DCD776 to say which of the three has happened — the only symptom the drill gives is stopping.

That’s the detail worth knowing before assuming the drill has failed: this is the battery pack’s own protection circuit acting to prevent damage, not a fault developing in the tool.

Working through it

Check the obvious first — that the battery pack is fully seated and clicked home, since a pack that isn’t properly connected can cut power in a way that looks identical to a protection trip.

If the pack is seated properly, try the trigger once rather than repeatedly. DeWalt doesn’t describe a reset sequence, a wait time, or a button to press: the documented fix is to put the battery on the charger and leave it until it reaches a full charge. A quick top-up isn’t what the manual describes, so give it the time to finish properly before trying the drill again.

Verdict

Free, and it’s meant to happen this way — the Electronic Protection System is there to stop the battery being damaged by exactly the conditions that trip it, not a sign the drill needs repairing. A full charge clears every case DeWalt documents for this symptom. If the drill still won’t run once a battery has come off a genuine full charge, swap in a second XR pack before spending on anything else — DeWalt’s own documentation has nothing further to check beyond the protection system, so a drill that fails on two different fully-charged packs is a service-centre question, not one to keep testing at home.