What should be done to repair an electric angle grinder if it stops working?

Next, you can check according to the following steps:

1. Check the switch:
   When pressing the switch, listen for a “click” sound. If there is no sound, the switch may have poor contact or be damaged. You can open the housing (disconnect the power first!) and check whether the metal contacts inside the switch are oxidized or deformed. Lightly polish any oxidized parts with sandpaper. If this does not work, the switch may need to be replaced.

2. Check the carbon brushes:
   Most angle grinders use carbon brushes. Remove the rear cover and locate the brush holders on both sides of the motor. Take out the carbon brushes and check whether they are excessively worn (replacement is recommended if the length is less than 5 mm), or if there is poor contact between the brushes and the commutator. Clean any dust inside the brush holders.

3. Check the motor windings:
   If the above checks show no issues, the motor windings may be open-circuited or short-circuited. Use a multimeter set to the resistance range to measure the resistance at both ends of the winding. If the resistance is infinite or close to zero, it indicates a winding fault. In this case, it is recommended to seek professional repair, as self-repair poses safety risks.

Note: Always disconnect the power during the entire process. Avoid touching metal components while operating. If you are not familiar with electrical circuits, do not disassemble the tool forcibly—seek help from a qualified professional in time.