FS is what controls match. Do you have a schematic you can post? And where is that Black-yellow wire? Pic?

I'd troubleshoot lack of game-over rather than lack of match. Does the Last Ball relay (BX) fire when your last ball drains? Does game over relay (Q) fire when last ball is drained?

From Bronco manual:

Screen Shot 2018-01-10 at 12.03.19 PM (resized).png

Screen Shot 2018-01-10 at 12.16.21 PM (resized).png

Screen Shot 2018-01-10 at 12.17.07 PM (resized).png

Then I'd selectively jumper over these switches/wire segments looking for a faulty connection to the (Q) game over relay's OR-GR wire. (There is also a motor 1A switch that is farther down the right hand side of the page that is involved too).

Screen Shot 2018-01-11 at 10.03.03 AM (resized).png

So I missed the part about the black/yellow wire being loose. If that indeed is the BLK-YEL wire seen in the red path above, that would prevent all matching and game over-ing.

Here are pics of a Bronco coin unit that might help. Unfortunately I no longer have the game so cannot provide better pics.

4P game start (resized).png
1P game start (resized).png

"game over-ing"

Hi wizardblom
could You solve the problem ?
If not - look at the first JPG - it is made from jeffc 's picture in post-6 --- how are my "marked green" wires connected ? Look at the second JPG - the Coin-Unit in my Williams Shangri La --- I made a "green dot" - wire "Yellow" is screwed on to the housing - EVERYTHING METAL on the Unit happens to be "wire-yellow" --- in the upper right corner an enlarged pic "Ball-Count-Unit".
Well, my pin is a Williams - and the wire is the common Williams-Wire-Yellow --- but may want to look for in Your Bronco - for an screw with an washer and signs of "broken-off wire" ?

No luck (?) - the third JPG shows stuff "Coin-Unit" I have found in the Bronco-schematics. When a friend helps an pulls on the "Snow-Shoe-Wipers on the Coin-Unit" - You then learn about (as it is no longer funcioning due to pulling on the snowshoes): Which wires are for the lights - which wires are for "stepping to next player / next ball". This reduces the number on "wires in question on 'wire-black-yellow problem' " and You only must investigate on the remaining wires.

Sometimes we read on a schematics: "Due to wire shortages - color of wires in the pin may be other than shown in the schematics (we used whatever colors we had)" --- very much non-pleasing.

I agree with jeffc 's post-5. Greetings Rolf

0Coin-Unit-pinside-Work-01 (resized).jpg

0Williams-Shangri-La-Coin-Unit (resized).JPG

0Bronco-Work-01 (resized).jpg

two things... for the connection thru the chassis you will have a wire attached to a mounting lug of 1 of the coils (somebody mentioned pic from other side), this may be your black-yellow

and... in positioning the tab under the mounting screw, if you pull the jumper wire a little tight to the spring loaded shoe then the shoe no longer makes contact. Move the tab so its pointed towards the shoe and ensures slack in the jumper. I once made this mistake on a Diamond Jack and wondered why the roto stopped scoring...

aabronco (resized).JPG

Black/yellow should connect to one of the chassis bolts of that unit (I'm unclear from the schematic what it may be)

IMG_0319 (resized).JPG