Tools / Power Tools
Bosch Professional 120-LI Cordless Impact Wrench User Guide
Quick user guide for the Bosch Professional 120-LI cordless impact wrench (GDR 120-LI & GDS 120-LI). Includes assembly, operation, battery care, and troubleshooting.
Table of contents
Quick guide from the manual
This document provides essential instructions for the Bosch Professional 120-LI cordless impact wrench (models GDR 120-LI and GDS 120-LI). It covers safe operation, battery maintenance, and tool usage.
Device Description
The tool is designed for driving and loosening screws and bolts, as well as tightening and loosening nuts within the specified dimensions. It features an integrated LED light for illuminating the work area.
Assembly
Removing the Battery: Press the unlocking buttons and pull the battery downwards out of the tool. Do not use force.
Changing the Tool: Always remove the battery before performing any work on the tool. For the GDR 120-LI, pull the locking sleeve forward to insert or remove the bit. For the GDS 120-LI, slide the application tool onto the square drive of the tool holder.
Operation
Inserting the Battery: Set the rotational direction switch to the center position to prevent accidental starting. Slide the charged battery into the base of the tool until it locks securely.
Rotational Direction: Use the rotational direction switch to change the direction. Right rotation is for driving screws and tightening nuts; left rotation is for loosening them.
Mechanical Gear Selection: Use the gear selector only when the machine is at a standstill. Gear I is for low speed (screwdriving/large diameters), and Gear II is for high speed (small diameters).
Switching On/Off: Press and hold the On/Off switch to start. Release it to stop. The integrated light turns on when the switch is pressed.
Maintenance and Cleaning
Regularly clean the ventilation slots to prevent dust accumulation, which can cause electrical hazards. Always remove the battery before maintenance or transport.
Technical Data
The tool operates at 12V. It features two speed settings (0-1300 min-1 and 0-2600 min-1) and two impact rate settings (0-1900 min-1 and 0-3200 min-1). The maximum torque for hard screwdriving is 100 Nm (GDR) or 105 Nm (GDS).
Manufacturer information
Bosch
Practical help
Common problems
Tool stops automatically
The battery is empty or the tool is overloaded. The Electronic Cell Protection (ECP) has triggered. Let the battery cool down or recharge it.
Gear selector cannot be pushed to the stop
Turn the drill chuck slightly with the drill bit to align the gears.
Before use
- Ensure the battery is fully charged.
- Set the rotational direction switch to the center position.
- Check that the correct application tool is securely attached.
- Ensure the gear selector is set to the desired speed range.
Specs in practice
- Rated Voltage
- 12V DC, compatible with Bosch GBA 12V batteries.
Model compatibility
- Use only recommended GBA 12V batteries.
- Use only recommended GAL 12.. CV chargers.
- Performance is limited at temperatures below 0°C.
Manual page author
Emily Carter
User documentation editor
Prepares concise manual descriptions and highlights the most useful setup, operation, and maintenance information for readers.