Learn how to troubleshoot your charge controller by checking for loose wires and observing LED light colors. Use a multimeter to compare the PV terminal voltage with the solar panel's operating voltage. If they match within a +/- 10% range, it's fine. If not, troubleshoot the panels. Check the battery terminal voltage and ensure it aligns with the float or boost voltage specified in the controller's manual. If it doesn't, seek professional assistance.