Those power supply regulated voltages are OK.
pin 15 MAY be a symptom, the 24v is not pulling enough current - i.e. something ain't running.
pin 15 runs the phono preamp and control amp. Neither would easily inspire the protect TO protect (by not pulling in the relay)..
Need you to measure and post the bare metal chassis ground referenced voltages you find on these pins:
AWM-062 protection board
pin 1 audio input, good would be dc millivolts, bad can go up to over 30v
pin 2 -13.6v dc
pin 3 audio input, good would be dc millivolts, bad can go up to over 30v
pin 4 ground zero ohms to bare metal chassis
pin 5 audio over-current protection input, good would be dc millivolts, bad can go up to over 30v
pin 6 audio over-current protection input, good would be dc millivolts, bad can go up to over 30v
pin 7 audio over-current protection input, good would be dc millivolts, bad can go up to over 30v
pin 8 audio over-current protection input, good would be dc millivolts, bad can go up to over 30v
pin 9 +36.5v dc with relay open, 10v with relay pulled in
pin 10 +36.5v dc
pin 11 +36.5v dc
pin 12 7.5v AC <<<<<<<<<<<<<<< SWITCH YOUR METER OVER TO READ AC VOLTAGES!!!!!!!!!
Then if you find pin 12 HAS the 7/5v AC on it, then you need to read the DC voltage found on the junction point of C5 (minus terminal) R34 and R25 : it should be -5.1 volts and it is crucial.