I can join the club now. Im having issues with my backbox GI, if anyone is in the system 3 thread some of it is posted there (i have a lot more to share but didnt wanna clog thread). It sucks because I just LED'd the game and really would love to see this backbox.

I have the manual. And the back box did not work with the regular lamps before I switched to LED

So here is my dilema. using the schematics and testing.

At the a12J1 connector from transformer I get 7VAC at pins 3/4/12/13.

Going to the next connector in the link A9J3 Pins 1&10 should be 6VAC and I do in fact get 7VAC here.

Then moving to the switch on Relay A. this is where my problem is:

When the switch is the OPEN top lug gives 7.0 and the Bottom lug gives 0.1

When the switch is CLOSED both lugs read 2.1.

Pins 3&12 on the A9J3 should read 6VAC because this is after the relay but because my switch they read 2.1.

The Coil on the relay does not read anything if I have the black probe touching the common wire and the red probe touching either lug of the coil.

I am also getting 2.1 at the backbox on each and every lamp. No where near the 6VAC I need.

On my tee'd off I get vastly different readings.

*I have cleaned the switch, no change.
*I have jumpered the switch lugs, no change.

I believe the flashers run through T relay. And they're working at this time.

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just ordered a new relay coil, hope this helps my issue with backbox gi

Sigh. Replaced the coil relay. Still no change. Still no back box lights. Same voltage readings.

Well I unplugged every bulb in the backbox gi, when I do this I get correct voltage when the switch closed (6v).

As soon as I add 1 bulb anywhere in the back box it drops to 3v

I tried about 5 of them. All same result

I did make sure the contacts were cleaned and adjusted correctly, That was the first thing I did before all this testing.

All the sockets look great. which sucks because I am not sure how to tell if one is shorted.

Also the fuse is correct, I made sure of that and testing it inside the system and outside the system. 15A normal fuse in spot F8.

How can I go about testing the sockets?

I can snap a picture later on tonight, but I honestly don't think they have them. There's one big diode connected to 2 ground wires, but the sockets just have a white and black wire in the back of them

Here's some

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Yeah I can try and unscrew from the last row forward see if anything changes. I will also test resistance.

Ok so tested the resistance, and there all the same. They all read 192 on my meter when set to 20k ohms.

Also I tried disconnecting the chains. Even with disconnecting all of them up to the last one no change on voltage

I believe all the striped wires are the flashers, nothing is missing from the harness

I can try that second thing you mentioned

Oh that is correct, I think that's the power wires from harness

I'm taking a break from working on the GI. Im pretty hopeless on it.

What's some high scores?? I have yet to hit dream warriors mode. And never got to trade the krugerands. But so far around 250k is my high score. This game is a blast when u get 4 ball multiball going

I'm thinking I'm gonna try and switch the transformer out of my teed off into freddy to see if that fixes the backbox GI.

This sound like a good idea?

Well I did this tonight and sane issue. So I know it's not in the first chain of sockets.

So my issue is elsewhere. I'm debating changing the transformer to narrow that out. It's only a few plugs and 4 bolts but ugh I'm not in the mood to take apart 2 games

Ok so now testing those wires. They both have the same reading. Around 5v. Like 4.8 when the switch is closed

My teed off is entirely different I'll include a picture. On teed off the double wires go through the chain a lot more than just the beginning but teed off uses all 44lamps, freddy uses 555s.

So now I get about 5v at the wires. But 2.1 when the lamps are hooked up. Even if it's just one lamp

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Can anyone please post a picture of there backbox? The inside where the lights are.

I want to make sure those striped wires are in the correct spot

Finnflash thanks so much, it's the same backbox. If you meant compared to the pictures on this page a few posts up, that's my tee'd off backbox. I posted my freddy backbox on the last page.

But that did confirm my wires are correct, so I gotta keep looking.