the drill just stopped in the middle of driving a screw and now it only makes a clicking sound when i pull the trigger

Diagnosis

The clicking sound you are hearing is the electronic overload protection circuit (thermal cutoff) engaging and disengaging rapidly. On the Ryobi ONE+ HP 18V Brushless Drill (PBLDD01B), the brushless controller monitors the current draw and internal temperature of the motor windings. When you hit a hard knot in the wood or drive a screw that is too large for the pilot hole, the amperage spikes beyond the safe threshold, triggering a safety shutdown to prevent the motor windings from melting. This specific "clicking" occurs because the trigger is still being depressed, causing the controller to attempt a restart, only to immediately trip again because the motor is still stalled against the resistance of the screw. This creates a rapid cycle of power-on and power-off. You can confirm this is the issue if the tool worked perfectly until the exact moment of high resistance and if the battery is known to be fully charged.

How to Fix It

To reset the electronic controller and clear the fault, follow these precise steps:

1. Immediately release the trigger and remove the 18V ONE+ battery pack from the base of the handle to completely kill power to the logic board.
2. Using a pair of pliers or a manual screwdriver, back the screw out of the material by a quarter-turn to relieve the mechanical tension on the drill chuck.
3. Allow the tool to sit idle for at least 3 to 5 minutes. This is critical because the brushless controller will not reset if the internal thermistor still detects a temperature above the safety limit.
4. Inspect the drill bit or driver bit for any signs of warping or overheating (discoloration). Replace the bit if it has been stressed.
5. Reinsert the battery pack, ensuring it clicks firmly into the locking lugs.
6. Squeeze the trigger lightly to confirm the motor engages before returning to the workpiece.

If That Didn't Work

• Check for Battery Cell Failure: If the clicking persists even with no load, one of the cells in your 18V battery may have dropped below the critical voltage threshold. Try swapping in a known-working High Performance (HP) battery. If the tool works with a different battery, the original pack has a failed cell or a tripped internal BMS (Battery Management System).
• Inspect the Trigger Switch Assembly: The PBLDD01B uses a variable speed trigger that can accumulate sawdust and debris inside the housing. If a particle is lodged in the trigger mechanism, it can cause an intermittent connection that mimics the overload click. Use compressed air to blow out the trigger gap and the vents around the motor housing.
• Verify Torque Clutch Setting: Ensure the torque adjustment collar is not set to the "Drill" icon (the drill bit symbol) when driving large screws into hardwood. Switch the collar to a medium-numbered setting (e.g., 10-15). This allows the mechanical clutch to slip before the electronic overload protection trips.
• Check for Internal Gear Binding: If the tool clicks without a battery but with a manual turn of the chuck, the planetary gear set may have a broken tooth or a jammed piece of debris. This requires opening the casing to inspect the gear grease for metal shavings.

Heads Up

• Avoid "Stall-Driving": Never force the drill to a complete stop while the trigger is fully depressed; this is the fastest way to wear out the brushless controller.
• Pilot Holes are Mandatory: When using the HP series for large fasteners, always drill a pilot hole slightly smaller than the screw shank to reduce the amperage draw.
• Heat Dissipation: If you are doing high-volume driving, pause every 10 minutes to let the vents clear. Brushless motors are efficient, but the compact housing of the PBLDD01B can trap heat quickly.
• Battery Compatibility: While this tool works with all ONE+ batteries, using the "High Performance" (HP) batteries provides more consistent current, which reduces the frequency of electronic trips during heavy loads.