I've had my FT for a few months now and some of you may know that I have to remove the head of a pinball to get in and out of my small London flat. Anyway, The seller kindly dismantled before pickup and labelled the connectors for me. Upon reassembly all was well apart from one problem. Half of the GI is on full power permanantly no matter what. I've uploaded a short video to demonstrate the areas affected. Obviously this doesn't affect gameplay much at all so I've just put off fixing it but I'm ready to try to get to the root of it. I have checked the connections and don't see anything too obvious but I'd appreciate some suggestions on what might be causing it.

The GI affected is most obvious at 0m48s when video mode starts and all PF and GI lights should go out.

Oops. Set to public now.

I have checked those connectors already but they seem fine to me and wiggling doesn't affect it.

The previous owner swears there was no problem and he's a decent sort so I believe him.

Cheers. I'll try all those but it's late now and I can't mess about with it until tomorrow unfortunately.

Did anyone watch the vid? The GI definately isn't supposed to do that is it?

Bump

Apologies to those that gave me advice but I haven't got around to having a good look at it until now.

From what people have said, I am thinking that the GI connectors may have some misconnected wires. J120 and J121 are both replacement connectors and both had loose wires and browning. I think maybe when the backbox was removed one or more of the wires may have come out and been replaced in the wrong section. This is based on the assumption that the GI was working correctly for the previous owner.

I have a crimping tool so I can redo those sockets but I'm not sure how to identify which wire should go in where. I have the manual but I struggle to understand it. Maybe a photograph would help?

Update

I'm slightly annoyed now as I found the right page in the manual and redid all the connections for J120 and J121. I was briefly excited to see the GI not come on full power immediately like it has been but then disappointed as I've realised now that GI isn't coming on at all. Also, the fish topper is off too.

I'm going to fiddle about with a few of the suggestions here but I'm getting frustrated. I'm realised I'm not a fan of fixing pinball myself. I like collecting, admiring, playing and watching other people fix them.

Well it's none of the lower GI.

They all seem fine when I use my multimeter on them.

All looks fine although I'm not sure what I'm looking for. All the heatsinks seem equally hot though.

I checked J113 and I'm pretty sure it's connected OK. I disconnected and reconnected a few times. I'm not sure how to check the driver transistor or triac or the 74LS374 IC chip.

He swears there were no issues. There are a few other 'quirks' that might be connected. The lower half of the backbox lights used to be glitchy and would only come on if you wiggled them. Since I rewired the connectors they are all on but solidly. Also, the DMD doesn't always display all the dots, especially during boot up, almost like it needs to warm up first. Lastly, the fish topper doesn't light up any more. It used to light up and respond to the game but recently I noticed it had gone off but came back on if you pulled out the right side of J121. Since my rewiring it is off all the time.

I did swap the J120 and J121 but nothing much seems to change.

I'm suspicious that when I attached new crimps to the wires I may have done one or more badly. I might have to go back and make sure they are contacting properly. Is there a way to do this without physically removing them and looking?

Update: Thanks to Pin_Crazed's pics I realised that I had connected the wires in J121 back to front due to not understanding which end was which. Unfortunately redoing it has only returned it to it's original state. So now I have the lower GI on permanently and on full with everything else working normally including the topper lights.

Bit stuck again after all that and back to square one. I should probably double check all my connections on J120 and J121 and perhaps redo some crimping..

I'm open to other suggestions still.