Marshall JCM2000 TSL100 Footswitch problems

[cablercdd1]

Anyone have experience troubleshooting a non working 5 switch footswitch for the TSL100? I haven't been able to find a schematic for the footswitch so I'm having trouble tracing the problem. The led for the clean channel works when that is pressed but when I press the lead or crunch switches the clean led goes out but the others don't light. The footswitch uses a Nand Gate which seems to be working then the output for all three preamp functions appears to go through a white wire to the din plug on the amp. From there I can't follow the schematic because they seem to be changing the connector #'s with no reference. I'm quite familiar with american brand schematics but I haven't figured out the Brit ones yet. Anyway any advice on how to troubleshoot this would be helpful
Thanks
Paul

[Jazz P Bass]

All that I have is:



If you are a member: MarshallForum.com

All the footswitch does is ground out each function.

Can you point out where the Nand gate is ? (page#/ coordinates)

[cablercdd1]

The nand gate is actually on the footswitch circuit board along with 3 transistors, a darlington pair and some caps and resistors. The 3 preamp control switches are momentary contact switches feeding into the Nand gate. The reverb and FX switches are 2P2T.
So far I can't find anything about the footswitch online. I just became a member of the Marshall forum so thanks for that info. I'll dig in deeper tonight when I get back home.

[g1]

I just became a member of the Marshall forum so thanks for that info. I'll dig in deeper tonight when I get back home.

See if these are any good: MarshallForum.com - View Single Post - TSL100 Footswitch schematics (new member)

[cablercdd1]

That's great, They had the schematic for the footswitch. That should help me trace the problem. Thanks

[Jazz P Bass]

Uhmmm...
Can you post it?

Edit: Joined and have it.

[cablercdd1]

Well I discovered that 2 buttons on the amp head have to be pushed in for the footswitch to work. One of the original problems was I had a bad LED as well as not having the buttons pushed in. I'm not sure if I inadvertently fixed the switching problem or the owner of the amp didn't know to push the 2 switches. I should have downloaded and read the owners manual before I started. Lesson learned. Thanks for everyone's help

[Jazz P Bass]

Who reads the manuals????

[bsco]

Who reads the manuals????

Actually I got caught like this a few times in the past....Now I download the user manual and take a quick look...I had a Marshall mini stack that had a footswitch problem.....the foot switch was supposed to be programmed from the factory to a set of defaults....this one was not and I never knew until I read the manual....I thought there was a problem with the switch assy....so now, whenever I get something that I am not totally familiar with I search for the owners manual first before I even open it up....