To work correctly it has to be inline between the solar and the MPPT controller that converts the solar voltage into the proper voltage to maintain the batteries. I would start at the battery and look for a connection the controller then go upstream from there.
2017 SLX 195RB
2021 Jeep Grand Cherokee Summit L 5.7L V8
Andersen WDH hitch, Renogy 100 AH Lithium &
200 Watts solar panels from Renogy
Prev. '14 Jeep Grand Cherokee Overland, gas 3.6 V6