For Q16 the emitter is common so verify continuity to emitters of Q17, Q9 and Q8, collector to 1J12-4, base to SR5 pin 5 or Q12 emitter.

For Q12 you can verify continuity for the collector at R42 and the Base at SR4 pin 4 or U18 pin 8

Use the known good circuits above and below Q16 (Q8, Q9, and Q17) to verify you are testing continuity correctly and also to verify your soldering is not shorted anywhere. Again use the other circuits to validate the readings you get - the 4 circuits should all read the same.

Post pictures of your solder work at Q12 and Q16, both sides of the board, just in case its something obvious

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