{"product_id":"williams-system-3-11-data-east-switch-matrix-harness-tester","title":"Williams System 3–11 \u0026 Data East Switch Matrix Harness Tester","description":"\u003cp data-lfile-container=\"1caa4aec-4e1b-4b2d-821e-244b549306e8\" data-pm-slice=\"1 1 []\"\u003e\u003cstrong\u003eDescription:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eTrack down a bad switch, a miswired harness, or a bent playfield contact on your pinball's switch matrix in seconds — no schematic, no multimeter, no guesswork. Plug this tester into the switch matrix harness (J10 for rows \/ J8 for columns on Williams, CN10\/CN8 on Data East) in place of the MPU or driver board, and closing any playfield switch lights up the matching Row and Column LED. A printed matrix silkscreened right on the board (switches 1–64, laid out by row and column) lets you read off exactly which switch number just closed, instantly.\u003c\/p\u003e\n\u003cp\u003eUnlike testers that plug into the MPU or driver board, this one tests the playfield itself — which means it works just as well with the playfield completely out of the cabinet. That's especially useful during a restoration: mount the playfield on a rotisserie, plug this in, and troubleshoot every switch while everything is still easily reachable, with no cabinet in the way and no driver board connected at all.\u003c\/p\u003e\n\u003cp\u003eFully passive — powered by a 9V battery (not included), nothing to configure, nothing to charge. Press a switch, read the LEDs, move on.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow to use it:\u003c\/strong\u003e\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003eDisconnect the switch matrix harness (J10\/J8 on Williams, CN10\/CN8 on Data East) from the MPU or driver board.\u003c\/li\u003e\n\u003cli\u003ePlug the Switch Matrix Harness Tester onto those same headers — works whether the playfield is in the cabinet or off it entirely.\u003c\/li\u003e\n\u003cli\u003eClose a switch on the playfield (by hand, or by tilting\/activating it normally). The matching Row and Column LEDs light up.\u003c\/li\u003e\n\u003cli\u003eCross-reference the lit Row\/Column against the printed switch-number matrix on the board to identify exactly which switch (1–64) just closed.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cstrong\u003eCompatible with:\u003c\/strong\u003e Williams System 3, 4, 6, 7, 9, and 11 (Williams never produced a System 5, 8, or 10 — despite what the numbering might suggest); Data East\u003c\/p\u003e\n\u003cp data-lfile-container=\"1caa4aec-4e1b-4b2d-821e-244b549306e8\" data-pm-slice=\"1 1 []\"\u003eSee it in action:  https:\/\/youtu.be\/NmYAcus2Frs\u003c\/p\u003e\n\u003cp data-lfile-container=\"1caa4aec-4e1b-4b2d-821e-244b549306e8\" data-pm-slice=\"1 1 []\"\u003e\u003ciframe width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/NmYAcus2Frs?si=ZNyH43LADvWuEBb4\" title=\"YouTube video player\"\u003e\u003c\/iframe\u003e\u003c\/p\u003e\n\u003cp data-lfile-container=\"1caa4aec-4e1b-4b2d-821e-244b549306e8\" data-pm-slice=\"1 1 []\"\u003eSKU:  TBD\u003c\/p\u003e","brand":"That Old Pinball","offers":[{"title":"Default Title","offer_id":68062193189160,"sku":null,"price":30.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0861\/0037\/7896\/files\/SwitchHarnessTester1.jpg?v=1793492002","url":"https:\/\/thatoldpinball.com\/products\/williams-system-3-11-data-east-switch-matrix-harness-tester","provider":"That Old Pinball","version":"1.0","type":"link"}