System 1 power supply (Dragon) - no neg 12v out

alejandromad

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So I got this Dragon pin and it only had GI lighting
I found it had no 5 V out on A2P2

Bought a Big Daddy's System-1 Power Supply repair kit and installed all the components. I checked all the transistors (Q1, Q2, Q3 and Q4) to make sure they weren't shorted to ground before installing it.

I installed it and found it is missing the -12 V
With only A2 P1 connected:
The LM7912 Regulator (LIC1) has nothing out of pin 2
pin 1 and pin 3 are reading correct voltages

How can I troubleshoot it further to determine if it's a bad LM7912 or maybe something in the crowbar circuit... SCR201 for example?
 
lm7912

Something does not sound right. If you look at the datasheet: pin 1 is gnd, pin 2 is input and pin 3 is output. I worked on mine once and the silicon pad fell out and I did not notice it. The tab is not case ground. If the pad is missing or the plastic washer is not installed correctly, the device will not function properly.
 
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