DIAGNOSIS Dirt, sawdust, and dried grease have packed into the sliding switch mechanism, creating friction.
FIX Flush the switch without disassembly.
- Move the switch to the center (lock) position.
- Spray a generous amount of electrical contact cleaner into the seams around the switch slider.
- Immediately work the switch back and forth between forward and reverse 20-30 times to clear debris.
- Wipe away excess and let dry for 5 minutes.
IF THAT DIDN'T WORK The detent spring or ball bearing inside the switch mechanism may be damaged or corroded. This requires opening the housing to inspect and likely replace the entire switch assembly (part of the trigger module).
HEADS UP Never use WD-40 or lubricating oil here—it attracts more dust and gums up faster. Use a cleaner that evaporates completely and leaves no residue.