Check the solder joints on that aux board. Those .156 connectors like to crack. If none of the chaser lights work that is most likely the problem.

It's obvious, but you may need a magnifier to see it. Google 'cracked solder joints' and you'll see what I'm talking about.

Big Daddy Enterprises has an Aux Lamp Driver board kit. I had a similar issue on an EBD and that fixed the problem.

The chase light board on my Data East Star Trek worked fine. It wasn't until I pulled the MPU that I discovered the IDC connector that serves the 3 leads to the light board were fried from a previous overload. So if you test your light board and find it to be funtional, chances are it's not getting power fed to it from the MPU.

Whenever I encounter a problem like this it's my first objective to pull the MPU and check the solder side to see if there are any hacks, burns, broken traces, etc. This can save HUGE amounts of time and trouble. In my case, I eventually had to replace the MPU, due to its being scorched and hacked throughout particular circuits. There was never a problem with the chase light board.

In fact, I had a reset problem with my STTNG. I pulled the MPU and found C5 had been replaced, but its trace to its corresponding bridge was fried and a jumper had been installed, however, rather loosely. Upon cleaning and re-soldering the joint I had no more resets. Hope this helps.

I should have mentioned that before pulling the MPU, try testing the power leads to the chase light board and make sure it's getting the proper power. I know that's a "no brainer" for a lot of folks but it's easy to overlook basics when you're chasing a ghost around in the machine. I know... I've done this.

In Space Invaders, the power for the aux lamp driver originates from the solenoid driver board. The regular lamp driver board uses the same feed, so if your feature lamps work, your chaser lights should also work unless there is a broken connection between the lamp driver and aux lamp driver. This could be a broken wire, which is unlikely since the harness *should* be clamped to the inside of the backbox. It could be a broken molex pin, which is possible, but these lamps don't draw that much current to burn up a connector and the .156 pins don't typically break like their .100 brethren. Or it could be a cracked solder joint on the .156 header, which is very common.

I would start by pulling the aux lamp driver and reflowing all of the .156 headers. Even if they look ok I would just do it. Then check for 5V on J1 pin 11. If that's good and still no lights, then start checking the individual components on the board or just shotgun everything with the Big Daddy kit like Matt said.

I will say 9 times out of 10 it will be the headers or a bad connector (sorry Matt, you got the bad one in the bunch.) If you ever watch ebay or swap meets you'll see lamp driver boards always available and selling for peanuts. They just rarely ever go bad and people don't need them. Same would probably be true of the aux drivers if Bally had used .100 connectors instead.

cracked solder.jpg

While cracked solder joints on this single sided PCB are the absolute most common failure, this board does suffer from other somewhat common failures.... Do the easy stuff first though.

I bought this pin last week but haven't gotten around to chasing (ha!) down the chaser light issue.

Thanks for all the tips - this is the best place for pinball on the nets.

So, I re flowed all the heads and am showing 4.7V on pin 11.

Is this enough? Thoughts on what else this could be?

I am really hesitant to replace the whole board as all the boards on this machine are original and in pretty fantastic shape.