Quoted from Quench:

Much better fault report.
There are four momentary solenoid select signals from the MPU board to the SDB. These are signals PB0, PB1, PB2 and PB3 which come from pins 4, 3, 2, 1 respectively on J4 of the MPU board and go to pins 6, 5, 4, 3 respectively at J4 of the SDB.
From the Solenoid Driver Board (SDB) schematic, below are the four PB0, PB1, PB2 and PB3 signal states and which solenoids the combination of states select. The four digits in the left column are binary numbers - "0" means zero volts, "1" means 5 volts.
One of these four signals is not reaching the SDB circuit. The solenoids listed on the left are what should activate, the solenoids on the right are what you are getting.
It is clear the PB3 signal is not getting from the MPU board to the SDB. This is a red-white wire from MPU J4 Pin 1 to the SDB J4 Pin 3. So you need to find out where the break in connection is - most likely one end of that wire has been badly crimped or the pin on SDB J4 pin 3 needs to be resoldered.
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