Controlling the Function Using Speed Change
Make sure that any socket is firmly attached. The tool should run at reduced speed.
Run the tool in the air (A).
With the reversing knob in reversing direction, pull the trigger and (with trigger still pressed) quickly pull the reversing knob to forward direction. (B) The AutoTrim valve should then switch from reduced to full speed. If the tool is running with full speed at (A) or still remaining at reduced speed at (B) the AutoTrim valve is in need of adjustment or service, see Adjusting the Switch Point.