Working on a NGG and having issues with the GI. Only one side of the playfield lights up. The other side doesn't. I measured the voltage at the pins J105 and J106 a couple different ways and got the same results on both. First method: Ground black lead of DMM to ground test point, red lead touching each pin. From right to left I don't receive any reading on the two pins with the red line. The other pins I get 7.6 volts DC. Second method: Touch black lead to first (right side) pin, then red to pins 6-10 and get 7.6 at each pin. Same is true for the other four pins on the right???!?!?! I thought maybe it was the molex connector so I snipped the wires for the GI section not working and touched them to their respective pin. No luck. However, I touch them to the pins for the working GI section and the lights work. So I know it is not a wiring issue but a board issue. I just don't understand why when I touch my black DMM lead on those two pins not working and touch the other pins on the left I get a reading? I guess I can pull off the board and check for a cracked solder joint. Any help?

I'll try this tonight. Honestly, I don't remember if I used AC of DC. Either way, I was getting 7.6 and nothing on the other measurement so I must have been doing it correctly. Lol.

Yes, did this with a meter. All good.

Just to be sure, the left side is out, correct? So that should be 7.6 ac. The right side pins are in? Use AC to test those? What should measurements be? Or am I just testing continuity at those pins to the nearest board component? I'd love to make sure it isn't the board.

Okay, did some additional testing. Voltage IN is good. Here is the perplexing issue. As stated, I feel there is an issue with the two pins I marked in red (2,3). It isn't a crack solder joint because I am having the same issue on the back box connector above. When I put my DMM meter on pins 2 and 8 I get 7.2 volts. Same with pins 3 and 9. Okay, voltage seems good. However, touching the bare wires to the pins won't illuminate the lights. However, if I run a jumper from the ground test point to the wire meant for pin 2 and touch the respective tracer wire to pin 8 the lights fire. Same with wires for 3 and 9. WTF. Has to be a board issue and I am assuming an amperage issue because the volts are reading correctly?

I'm assuming I need to check continuity between the J103 in to Q4 and Q3. Then check continuity from Q4 and Q3 to J105 and J106. If there is continuity it must be the triacs. Maybe I just run a jumper from J103 to J105?

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I'm getting 7.2 when I put my probe on pin 2 and 8. Each lead to a pin. No ground.