If you have not already done so, go to the HWH web site and download the trouble shooting guide and manuals for your system and start trouble shooting from there. I'm sure you've already rechecked all your electrical connections on the individual jack solenoids. A quick thing to do would be to switch connections with an adjacent jack solenoid and see if the problem transfers to the other solenoid.
Depending on the system you have, trouble shooting using the LED lights on the control panel will usually pinpoint the problem.
'07 Winnebago Journey 34H, ISB-02, MH2500
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US Gear UBS