Similar to this same question, I also have a B&D 24 volt grass trimmer that does not operate, no response even with a fully charged battery. Model NST 1024. Possibly a bad switch also. Only two years old..

SOURCE: CST1000 Black & Decker Cordless Trimmer/Edge won't start

http://www.toolpartsdirect.com/cgi-bin/schematic.cgi/blackdecker/CST2000_TYPE_1

Part number #243614-00.
It's a microswitch made by Honeywell that costs about 5 bucks plus shipping.
The attached file has the schematic and parts list.
The CST2000 is well worth spending a few bucks to keep it going. Finding a local B&D authorized service center near you will even save you the shipping as they can order it for you.
Every other component is pretty dependable- the motor, battery, wiring, charging system, spool system- all built to last.
Only down side is you really only get 20 to 25 minutes of hard weedwhacking before you need to recharge. Of course, it's time for a cold beer in the pool by then.

SOURCE: Can't find spool replacement AF-150-04

not sure but .065 maybe

SOURCE: I have a B&D Grass

Check your charger.

SOURCE: black and deck grasshog timmer battery not working

I had same issue-- I cleaned the whole thing and it seemed to be OK but especially in edger more it would not work. I kept fiddling with it and it would seem better, only to get worse...

What I did was take apart the lower unit-- there are something like 7 screws (be careful, I stripped one). Then you need to pry apart the plastic sides and pull out the little motor. I saw that from me continuously changing from edger to trimmer, the wiring became frayed. You'll notice there are two conatcts on top of the motor. In my case one was connected fine and the other was frayed. I went to Home Depot and bought some vynyl insulated 0.250" tab-female "Disconnect F" things (a pack of 10 cost 99 cents). I then stripped the wire and crimped it into this connecter thing and slid the female part over the contact. I squeezed as hard as I could in hopes of this repair lasting forever (crimping as well as "crimping" the femaale part over the contact).

Then put the motor back in. It first pulling the motor out seemed impossible, but it does fit; and I was able to get it back in.

It is as good as new now!

SOURCE: Owner's manual 18V cordless Black & Decker Grasshog grass trimmer

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