So I upgraded my TSPP to full LEDs using CoinTakers:

SIMPSONS PINBALL PARTY-1 LED Kit w Premium Non-Ghosting LEDs

The game looks amazing after the install but I noticed that there are many lights that are ghosting. I have version 5.0 CPU and Display roms. Is this normal? I guess I just figured that if I bought the non ghosting kit for my TSPP that I wouldn't have this problem.

In the attached video it shows the "shoot again" and the "spay anything" being dimly lit. Am I correct in thinking that these lights should not be lit up at all? It's not just these two lights either. There are multiple lights that light up dimly throughout the playfield.

http://vid1114.photobucket.com/albums/k534/jakescott81/TSPP%20Ghosting.mp4

There were no ghosting issues that I remember when I first brought the game home. I purchased it from a collector that meticulously takes care of his pins. The game only had 230 plays on it when I purchased it from him so I have a hard time believing that it's a hardware issue...but I am new to the world of pinball ownership so I could be completely wrong in thinking this. When I get home I'll replace one of the ghosting LEDs with an incandescent bulb and see what happens.

The only reason I upgraded to full LEDS in the first place was because 2 of the original bulbs went out within a few days of owning it. So instead of having to deal with all the 12-13 year old bulbs slowly burning out, I just replaced them all in one shot.

Please forgive my noob-like question, but what is the best way to search by row and matrix for a problem diode and how do I know if the diode is bad?

Thanks a lot guys. I know my way around fixing arcade machines but this pinball troubleshooting is all new to me.

The two bulbs that burned out were play field GI bulbs, not inserts. Would that make a difference?

Well I had some time this weekend to check out my ghosting issue. I went into single lamp diagnostic mode and found out that almost every light in the game makes another light ghost. Here are my findings:

The first number is the lamp that is supposed to be lit, then the name of the ghosting lamp with the number in parentheses.

11 ghosts shoot again (3)
15 ghosts light Otto (7)
16 ghosts adv pops (8)
17 ghosts spay anything (9)
18 ghosts kitty kitty bang bang (10)
19 ghosts field of screams (11)
20 ghosts esophagus now (12)
21 ghosts itchy/scratchy yellow arrow (13)
22 ghosts itchy/scratchy multiball (14)
23 ghosts itchy/scratchy 2x (15)
25 ghosts left pop bumper (17)
26 ghosts light (upper play field) (66)
28 ghosts more time arrow (20)
29 ghosts collect nuclear plant (21)
30 ghosts left orbit arrow (22)
31 ghosts Cletus 2x (23)
32 ghosts left orbit hurry up (24)
33 ghosts cbg skill shot (25)
34 ghosts cbg start hurry up (26)
35 ghosts purple ramps (27)
36 ghosts purple bumpers (28)
37 ghosts purple loops (29)
38 ghosts purple targets (30)
41 ghosts left ramp arrow (33)
42 ghosts treehouse of horror (34)
43 ghosts treehouse 2x (35)
44 ghosts left ramp hurry up (36)
45 ghosts right ramp arrow (37)
46 ghosts get duffed! (38)
47 ghosts Moes 2x (39)
48 ghosts right ramp hurry up (40)
49 ghosts mini loop arrow (41)
50 ghosts kwik e mart 2x (42)
51 ghosts kwik e mart hurry up (43)
54 ghosts garage 2x (46)
55 ghosts garage hurry up (47)
56 ghosts right orbit arrow (48)
57 ghosts right loop arrow (49)
58 ghosts ottos bus tours (50)
59 ghosts elementary 2x (51)
60 ghosts bully 3 bank TOP (52)
61 ghosts built 3 bank MIDDLE (53)
62 ghosts bully 3 bank BOTTOM (54)
63 ghosts krusty 2x (55)
64 ghosts right orbit hurry up (56)
65 ghosts homer face (57)
66 ghosts Marge face (58)
67 ghosts Bart face (59)
68 ghosts Lisa face (60)
69 ghosts Maggie face (61)
70 ghosts grandpa face (62)
73 ghosts living room 2x (65)
74 ghosts light upper playfield (66)
75 ghosts lock upper playfield (67)
76 ghosts big lock upper playfield (68)
77 ghosts super jackpot upper playfield (69)
78 ghosts upper playfield yellow arrow (70)

Holy....crap....

So I ended up ordering from LED OCD. It completely fixed all the ghosting issues. The inserts all fade nice and smooth now as well. Thanks!