This is an article with a checklist for a grass trimmer maintenance.

For your Husqvarna grass trimmer to work optimally, maintenance needs to be performed after set intervals. Some maintenance can be performed easily, and some needs to be carried out by an authorised dealer.
Weekly maintenance
Clean the external surfaces.
Check the idle speed.
Check the bevel gear grease. Monthly maintenance
Examine the starter rope handle and the starter rope. Yearly maintenance
Check the spark plug. How to clean or replace a spark plug
Apply grease to the end of the drive shaft (two-piece shaft).
Clean the external surfaces of the carburettor and its adjacent areas.
Clean the cooling system. How to clean the cooling system
Check the spark arrestor screen. What is the purpose of a spark arrestor
Check the fuel filter.
Examine the fuel hose for damage and cracks.
Examine all cables and connections.
Maintenance tasks after 50 hours of operation should be done by an approved Husqvarna dealer.
WARNING: Remove the battery before you perform any maintenance.
Daily maintenance
Clean the external parts of the product with a dry cloth. Do not use water.
Check that the START and STOP button works and that it is not damaged.
Make sure that the power trigger and the power trigger lockout function correctly.
Make sure that all controls work and are not damaged.
Keep the handles dry, clean and free from oil and grease.
Make sure that the cutting attachment is not damaged. Replace if you see any cracks or damage.
Make sure that the cutting attachment guard or blade are not damaged. Replace if you see any cracks or damage.
Make sure that the screws and nuts are tight.
Make sure that the suspension ring is not damaged.
Make sure that the handle and the handlebar are not damaged and are attached correctly.
Make sure that the blade is correctly centred, is sharp and is not damaged.
Make sure that the locknut of the cutting equipment is tightened correctly. Weekly maintenance
Check all couplings and connections. They should not be damaged and/or dirty.
Make sure that the bevel gear is correctly filled with grease.
Make sure that the air intake of the motor is not dirty. Clean the air intake with compressed air. Monthly maintenance
Check the connections between the battery and the product.
Make sure that the safety release on the harness is not damaged and operates correctly.