Jump to content

JS365 Bosch Jigsaw- Speed control failure?


Recommended Posts

I have replaced the switch and still no power. I suspect the speed control board.

      Can I short out/disconnect the board so that the unit runs at full speed all the time? If so how? I do not want to spend the money for a new board after wasting it in a switch and the variable speed feature is not important to me. Thanks for help.


Link to comment
Share on other sites

I pulled up the parts breakdown on e replacements and it looks like the trigger feeds some some kind of range limiting board with a knob adjustment. Power directly to the motor should run it BUT your trigger is a speed control, not an on-off switch. That still leaves you without a power switch to run it at full power. I am sure you want some safe, convenient way to start and stop it. It could be the board but that is a hit or miss way to fix something. It is hard to troubleshoot on line so I hesitate to tell you what to do. A multimeter is the normal way to see where you lost power. Eyeballing will not always find the problem. If you are not comfortable measuring AC, stay out if there. One thing you might try us exercising the knob on the speed board. They can get flakey.

Sent from my SM-G900V using Tapatalk

Link to comment
Share on other sites

  • 1 year later...

Just had the same failure, on a GST 90BE, so posting this for reference for others.

Yes, you can bypass the the speed controller, and the switch will still work. Remove it and join the white wires and the black / blue wires. Soldered and sleeved in heat shrink tubing.

You should also add a 0.1mF X2 250v suppression capacitor across the 2 power lines, or you will get excessive sparking from the brushes.

The thin wires with the plug on the end can be left, they are the trigger speed control lines.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Member Statistics

    Total Members
    Most Online
    Newest Member
  • Create New...