We have a RYOBI Trimmer and the power switch on the trigger is not working. where can we pick up a switch The switch #0409 105A 125 Volt AC. RY41002 ALG 1870437 Ser. No. 1

There could be a few potential causes for this issue with your Ryobi battery-operated trimmer:

1. Battery issue: If the battery is low on charge or not able to provide enough power to the trimmer, it may shut down when operating at full throttle. Try charging the battery fully and see if the issue persists. If the battery is old or damaged, it may need to be replaced.
2. Overheating: If the trimmer motor or battery overheats, it may shut down to prevent damage. Try using the trimmer for shorter periods of time and allowing it to cool down between uses.
3. Trimmer head or cutting line issue: If the trimmer head or cutting line is damaged or worn, it may cause the motor to work harder than normal, leading to overheating and shutdown. Check the trimmer head and cutting line for damage and replace as necessary.
4. Trigger or motor issue: If the trigger or motor is faulty, it may cause the trimmer to shut down when operating at full throttle. Contact Ryobi customer support or a professional repair technician for assistance in diagnosing and repairing the issue.

Overall, it's best to start with the simplest potential causes first (such as the battery charge level or trimmer head condition) before moving on to more complex issues like faulty triggers or motors.

Question edited to add FULL make model (what it is).
Category moved from Washing Machines to Ryobi Trimmer.

Replace the spark plug. Strip and clean the carburetor. Replace the fuel with fresh. But hang on though, the RY40002 is electric and runs with a 40 volt battery, so no spark plug and carburetor! :>D Replace the battery, lubricate everything from the motor to the head. Check the motor with nothing attached to it. The carbon brushes may need replacing or its bearings need greasing.

Ryobi RY40002 40V Power Head and RY15523A Expand-It ...

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Try the battery in another Ryobi to see if it works.
If it does not work it may have been effected when the trimmer burnt out.
time to buy a new battery.

Line Trimmer Line Replacement of a Ryobi One+ 2013 ...

? 2:33
www.youtube.com/watch?v=8jEER8lHUQk
Feb 22, 2013 - Uploaded by TheLegoCityBoys How to replace line in a garden Line Trimmer. ... Ryobi 40-VoltLithium-Ion Cordless String Trimmer RY40210 - Real World Review & How To ...

I would say its the switch foe sure if you have a charged battery or a defective motor but sounds like switch to me

When looking at the head, you will see to two gray rectangle pieces. Press them both at the same time between your thumb and forefinger and then pull. It should come unlatched and reveal the line spool on the inside

Ryobi Trimmers unscrew halfway down the shaft (so it fits in the box). If this gets loose, the trimmer will stop working. Simply tighten the connection between the upper and lower half.

the wiring maybe disconnected, either at the switch or down near the head of the trimmer

TJ, I've had the same problem since yesterday and I found the solution (lots of googling - that's how I found your post BTW).
It turned out that the switch malfunction is a common problem.

The part number for the FA3-4 switch is:

ut41002a-36 ("switch assembly")

Available here (thru Amazon):
http://factorylawnandgarden.com/product/553902/B000PLVCX8/SWITCH_ASSEMBLY_UT41002A_36/

It's a Homelite part, which is identical to Ryobi.

Here is the manual showing it (part 6):
http://www.m-and-d.com/pdfs/ryobi_tool/RY41002.pdf

Here is the thread with the solution:
http://www.ryobitools.com/dc/dcboard.php?az=show_topic&forum=112&topic_id=597&mesg_id=597&page=3

HTH,
Adi

My straight shaft trimmer will idle but dies when the I pull the trigger.