Go to the test single lamp mode of one of the lamps that make the extra lamps light.

One by one, go down the column and take out each bulb. When you get to the one that is the problem only the light that is supposed to be lit will be. After that, figure out what the problem is... bad diode, wired to the wrong lug, circuit board problem, etc.

I had this problem with my TAF and it drove me nuts for the longest time. In the end it turned out that on one lamp they had soldered to the wrong lug, completely bypassing the diode (easy to spot and fix), the other was a phantom trace on one of my lighting boards (much more difficult to figure out). I actually had to scratch down into the board to sever a trace that wasn't supposed to be there.

Good luck!

Chris

People had me doing the same thing... Check all the transistors, use the meter, etc etc. Not saying that isn't the problem, but if you do the bulb check, one at a time, it eliminates the easy things first.

If you take each bulb in the column out, one at a time, and all of the lights stay lit the entire time THEN check the other things, but do the easy check first.

You are looking for things to be normal. For example... you have 11 lit and 21, 31, 41, 51 are all lit too. If you pull out 51 and the only one that stays lit is 11 you know that the problem is somewhere with 51.

You pull, 11 (replace), 21(replace), 31(replace), 41(replace)... nothing changes, but pull 51 and the only one that stays lit is 11, you found your problem.

Here are the threads from my problem:

First: http://pinside.com/pinball/forum/topic/help-me-understand-lighting-matrix

Second: http://pinside.com/pinball/forum/topic/fixed-lamp-problem-on-taf-almost-more-help-needed

Third: http://pinside.com/pinball/forum/topic/taf-lamps-work-lamps-work-lamps-work-lamps-work

If you read through those old posts, you will see that I was told exactly the same thing.

Not saying that this will absolutely solve his problem, but it is a whole lot easier to try this first BEFORE going in and just replacing board parts at random.

Worked for me TWICE on the same machine, so obviously this is not completely in left field.

If it doesn't work, meh.. Wasted all of about 15 minutes. Replacing parts on the board - days/weeks waiting for parts, then hoping it really is the problem. Worst case scenario... making the problem worse because the boards were not the problem in the first place.

I am far from an electronics expert, I just used logic to figure out what was wrong with my machine. As they say... "You're mileage may vary."