What's new
By:
Pinball info

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

STTNG: Switches 33, 43 oscillating open & closed

A

AD1

Registered
Joined
Nov 21, 2022
Messages
10
Location
northallerton
Hi,

Need a bit of guidance, my STTNG has delayed a new fault, the right gun is continually being fed and then fired. Game starts intermittently when rebooted.

The switch test shows that switches 33 & 43 are rapidly oscillating open and closed.

Wondered if it's a dying capacitor - any thoughts where I should start?

Thanks Al
 
I've never owned a sttng, but the wiring looms for the guns on this title are a very well known failure point.

www.pinball.co.uk

Cannon looms (pair) for Star Trek TNG H-17067 - Pinball Heaven

Replacement Star Trek TNG cannon looms. Improved cannon loom (pair/with connectors/fitting instructions) made in the UK by us for many years. Come with lifetime warranty (when fitted according to our instructions). Most intermittent cannon problems on Star Trek TNG pinball machine are down to...
www.pinball.co.uk www.pinball.co.uk

I'd consider pulling the relevant connector off the MPU board to isolate the physical switches in the playfield from the electronic brain of the game.

You can then test the mpu board is OK by going into switch test and manually shorting the relevant switch matrix pins on the board.

If the mpu is OK and removing the relevant connector eliminates the madness, it suggests you have a wiring loom problem.

I don't know whether the problem switches are optos? They are also a common source of woe and you may then need to replace the relevant opto chip.

Another possibility is battery leakage as that causes all manner of chaos
 
First port of call is look at the manual and the switch matrix, it’s been a long time since I owned a sttng but I think there are on the same row and right next to each over and under the playfield , it could be a couple of optos just dirty or the row wire touching something thing
 
Thanks for the ideas, the switches (both Opto's) are in the same row of the matrix, next to each other. I'll start with the opto's and row wire tomorrow if there's time when I get home.

thanks again for the pointers.

Al
 
Having owned the pain in the ⬇️ sttng and having to rebuild it all, The cannon loom wire can cause all sorts of strange issues, that will take you down a rabbit hole thinking it's something else, start with replacing that, pinball heaven used to sell them.
 
There tricky to fit, you have to soldier them in place to in the canon optos, the wiring was coloured wrong when I bought ithe replacement loom and had to swap it when it didn't work. Check the wire going from the molex to the wire that your soldering to make sure it's right, the colour on the star trek follow that the molex based upon the manual. Then solder the appropriate to positive or negative on the opto, black and red from memory
 
Last edited:
AD1 said:
The switch test shows that switches 33 & 43 are rapidly oscillating open and closed.

Wondered if it's a dying capacitor - any thoughts where I should start?
Click to expand...

Replace the capacitor on the opto board under the playfield. I would do this before replacing the cabin wiring. If it's leaked, clean up the mess and repair the track before putting back in the game.
 
You must log in or register to reply here.
Back
Top Bottom