I just put back together and Indiana Jones (WMS) after a playfield swap, and I have some issues

F116 fuse (3A SB) blows at power-on. It blows immediately every time the game is powered. All other fuses are intact, and have been verified for correct values.
Power Driver Board LED 7 (+12v DC) is off; all other LEDs are showing "normal" status on all boards.

Overall state of the game; quick observations:
> all mechanical switches seem to be working
> none of the opto switches seem to be working
> all solenoids seem OK, and respond to tests correctly
> motors (idol, Path of Adventure) do not work
> around a third of the controlled lamps do not seem to work; have not yet done a closer look whether this could be due to something simple like bad bulb connections
> Hand of Fate lights (in both left and right inlane) are locked on, right from the start

What should be the logical next steps to isolate the problem?

Any advice is greatly appreciated.

I guess as the first step to troubleshooting I would like to find out whether the problem is on the board (BR5 and its filter capacitor???) or perhaps a shorted opto or motor on the playfield?

In order to isolate the board, can someone suggest which connectors I have to remove to get the motors, optos and other 12v devices out of the loop?

With connectors J116, J117 and J118 all disconnected the F116 fuse no longer blows at game start.

Here are my test point voltages in this state of the game:

TP1 (+12v unregulated): 15.5v
TP2 (+5v): 4.98v
TP3 (+12v regulated): 11.9v
TP6 (+50v): 73.8v
TP7 (+20v): 21.9v
TP8 (+18v): 18.1v

Are those all within reasonable spec? If yes, what are the logical next steps for tracing the problem?

Edit: I plugged J117 back since this is the +12v feed to the Dot Matrix controller. The game still starts with fuse F116 intact and +12v alive on the power driver board, so it is down to J116 and J118....

On my game the wiring for both connectors seems the same thickness (with wires gray/yellow, black on he middle two connector pins). One of these is feeding the coin door, while the other goes to the playfield... it would be probably good to isolate it down to one.

I now have J116 plugged in to the connector feeding the playfield boards, and I am still good! Idol, Path of Adventure and opto switches now work....

Flipper buttons don't, but I assume that the "coin door" feed also powers flipper optos?

Edit: for clarification, on my game connector J116 was connected to the playfield feed originally, that is why I have it that way now. From your earlier comments I gather that this is OK and that J116/J118 are interchangeable?

If not, I can try moving the plug to J118 (which is also what the manual indicates as correct)

I had to run into town to buy some more 3A SB fuses... I depleted my stock while "testing".

Here is where I currently stand: I narrowed the problem down to the left flipper board connection. If that is plugged in, F116 blows with the usual symptoms.

I currently have the right flipper connection plugged in, while the left one is unplugged. In this state the unregulated 12v is good in the game. However, the right flipper board is not registering in switch edge tests, even with the connector in place.

I checked out the connector pins carefully, and they are correctly aligned... next step is to look at the traces. Are there any particular steps I should use to assess the flipper opto boards?

EDIT: more information... I switched the flipper opto boards (now the former left board is at right and the former right board is on the left).

The problem DOES NOT travel with the flipper opto boards. If I have either opto board connected to the left connector, the game blows a fuse. The right side does not register switch closings during switch edge tests regardless of which board I am trying, but it does not blow a fuse...

I think I just bumped into something super relevant... I can't believe I have not seen this thread earlier:

https://pinside.com/pinball/forum/topic/wpc-dmd-f116-keeps-blowing/

In this case the culprit was a disconnected(??) unsoldered(??) wire near the idol VUK.

I checked that, hoping to strike gold, but no obvious bad connections or hanging wires on my game. I tested all above-playfield and under-playfield optos in switch edge tests, and they all register. Still, the symptoms are dead identical.

No mods... game is factory original in most respects (other than it is a German re-import).

One thing that occurs to me... I have changed the original coin door. It had a two-lead Cherry switch for coin door interlock. It did not have the second interlock switch (most games produced for export did not).

Currently the Cherry switch is just hanging loose (I have a bracket on order that will actually make it functional).

Is it possible that there is an issue with this arrangement? See pic below.

IMG_0494.jpg

VICTORY!!!!!!

I was thinking about misbehaving or stressed switches, and it occurred to me that I had to use a lot of force to wrangle the Superball button into proper position. It is possible that something broke or shorted in the process....

So I just disconnected the Superball harness and PRESTO... no more F116 blows, and both flippers are connected and working like a champ!

I now just have to replace a couple of marginal mechanical switches, align the flippers and I should be good to go.

PinballManiac, you don't know how thankful I am for your babysitting me through my stupidity and working through this process. You were amazing and I hope I find some way to repay the favor someday.

superball (resized).JPG

Aaahhhh.... thanks so much guys,

believe it or not, I screwed that connection directly onto the braid because glancing at my teardown pictures it looked like it made contact. Looking again now, it was just dangerously close but not actually touching. I will fix that now...

Thanks again, everyone! First game is underway....