Do you have a voltmeter or a test light? Not absolutely necessary. IF you are extremely careful you can do a simple test to see which one may not be working. The large terminals are what get connected inside the solenoid. With a piece of scrap wire cut the insulation off the ends. Just a 1/4 inch is plenty. Then temporarily short across the large terminals to see if things come back on. Wear some gloves and be very cautious doing this.
If you determine one of the solenoids is not working be sure to disconnect both battery bank negative terminals before bypassing it.
Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate