We know now you have the correct voltage up to the power supply. Next you need to check how much voltage we are loosing through the pwr supply board and the PPB board.
it is normal to lose around out 0.5 between the G.I Input plug on the power supply & the G.I out puts (one on the power supply and the other om the PPB board).
check the voltage at the G.I. input on the Pwr supply board.
CN9 Y3 & W3
CN9 Y4 & W4
Next check the G.I. voltage coming out of the power supply
CN8 Pin 1 (Brown) & pin 6 (white / Brown)
Next check the G.I voltage out put on the power supply and PPB board
Pwr sup: CN8 Pin 1 (Brown) & PPB J5 Pin 5 (white / Brown)
Pwr sup: CN8 Pin 2 (yellow) & PPB J5 Pin 6 (white / YELLOW)
Pwr sup: CN8 pIN 3 (Green) & PPB J5 Pin 7 (white / Green)
Pwr sup: CN8 pIN 4 (violet) & PPB J5 Pin 9 (white / violet)
Again after I get these I will give you more instruction.
Just so you know i am trying to find out where the weak spots are that are causing the problem. It is a good idea to change the CN8 on the power supply. It maybe the plug you are changing or the tracks to and from the relay on the power supply board. or the plug for the fuses on the ppb. Also check the fuse clips on the ppp board. these fuse clips are know for thier cracking.
sorry it took so long to reply tonight.