Flash Gordon light problem

[Crashramp]

Hi guys, I've been trying to get this problem sorted over the weekend but haven't had any luck. I have 15 lights on the playfield and 11 in the backbox that keep dropping out. Every now and then they come back again but mostly they are out.
All boards on the game have been rebuilt but I tried swapping both the rectifier board and the lamp driver board over with spare boards I have without any luck. All 0.100 and 0.156 connectors in the game have been re pinned and I also re pinned the J3 and J4 backbox connectors to the Rectifier board. I haven't re pinned all of the 0.063 connectors but I did do one of the 24 pin ones in the backbox tonight because it was the only one which looked a bit iffy. Every connector in the game has also been re seated.
I have removed every one of the globes affected by the problem and tried placing them back in one by one to see if one of these was shorting something out. No luck there either.
Everything else in the game is working perfectly so I'm not sure where to go from here any advise or ideas would be greatly appreciated. Thanks.

[riverinapinball]

Are these gi lights. If so check f5 fuse on the power supply . Loose or bad fuse holder . It says  20amp fuse in the manual

[Crashramp]

Hi Dan, yes they are all GI lights. That 20amp fuse on the rectifier board was the one which blew the other week. It tests fine and I actually swapped the whole Rectifier board over for the one out of my Xenon which has the exact same board and unfortunately it didn't make any difference.

[Strangeways]

Sounds like one of the GI lamp sockets is shorted to ground. I had an issue with a Fathom once where all the GI lamps would dim ONLY when I closed the headbox light panel. Initially the GI fuse blew on power on. As I diagnosed the problem, the lamps were all working when the light panel was open and then immediately dim when I closed it. Open the door and back to normal. Close it and they all dim. Is was the lower common wire at the bottom of the lamp panel shorting against the earth strap of the head.

I would take the approach of splitting the problem by removing the connector for GI on the headbox. Then you know where the problem is - lower cab or headbox.

[Crashramp]

Thanks Nino, I'll give that a go.

[Crashramp]

This has really got me stumped. I've tried isolating the head box from the cabinet but the problem remains. The same lights still remain off on the playfield when the head box is isolated and vise versa. Occasionally they come back on but only for 10 seconds or so then they're gone again. I've been over the underside of the playfield and inside the backbox looking for anything out of place or touching so many times that I'm starting to see them in my sleep.
 I don't think its dodgy batch of globe holders either because there are three different types of holders involved, they all went at once and they all come back on together.
 

[Strangeways]

This has really got me stumped. I've tried isolating the head box from the cabinet but the problem remains. The same lights still remain off on the playfield when the head box is isolated and vise versa. Occasionally they come back on but only for 10 seconds or so then they're gone again. I've been over the underside of the playfield and inside the backbox looking for anything out of place or touching so many times that I'm starting to see them in my sleep.
 I don't think its dodgy batch of globe holders either because there are three different types of holders involved, they all went at once and they all come back on together.
 

That leaves the front door. Often corroded coin entrance lamp sockets ?

[Crashramp]

This has really got me stumped. I've tried isolating the head box from the cabinet but the problem remains. The same lights still remain off on the playfield when the head box is isolated and vise versa. Occasionally they come back on but only for 10 seconds or so then they're gone again. I've been over the underside of the playfield and inside the backbox looking for anything out of place or touching so many times that I'm starting to see them in my sleep.
 I don't think its dodgy batch of globe holders either because there are three different types of holders involved, they all went at once and they all come back on together.
 

That leaves the front door. Often corroded coin entrance lamp sockets ?

I didn't think it could be the coin door but I actually disconnected that today just for the hell of it. Made no difference unfortunately. 
I think I'm going to have to start from scratch again and just go over it as carefully as I can. At least I know the Lamp driver board and Rectifier board are good. Is there any other board which could cause a problem like this?

[Strangeways]

They are GI lights. So it won't be a board problem.

Just thinking out aloud - Have you upgraded to LEDS or replaced / adjusted anything recently ?

I'm thinking there is a short with a common group of GI lamps. A GI Common is shorting somewhere. Follow the GI braid and see if they are all related to the GI lamps that are out. It is going to be something simple. You just need to find it.

[Crashramp]

They are GI lights. So it won't be a board problem.

Just thinking out aloud - Have you upgraded to LEDS or replaced / adjusted anything recently ?

I'm thinking there is a short with a common group of GI lamps. A GI Common is shorting somewhere. Follow the GI braid and see if they are all related to the GI lamps that are out. It is going to be something simple. You just need to find it.

No, no LED's. The last thing I did was adjust a spoon switch on a pop bumper to try and get rid of a dead spot on it and It was about this time that the lights died. I figured this could have something to do with it but just can't seem to find anything which could be shorting it out.
Although the problem affects the backbox as well my gut feel is that the cause of the problem is something I've done below the playfield. Just have to find it.

[ddstoys]

Did you replace the pop bumper globe holders?   The originals in these can short out and e very sketchy

[Crashramp]

Did you replace the pop bumper globe holders?   The originals in these can short out and e very sketchy

Thanks Daniel,

I some how missed your post until now. I wasn't changing the globe holders but those Bally pop bumper globe holders are sensitive things aren't they. 
Fortunately the problem was solved tonight thanks to a second set of eyes. We swapped the Aux Lamp Board over with the one out of my Xenon and problem solved. It only seems to affect 1 bank of lights on the Xenon so the problems not fix but at least I know where it's coming from. It was driving me crazy scanning up and down the underside of the playfield and backbox looking for shorts so a big thanks to Blair (Pintoxicated) again for dropping by to help me out.