I meant fuses for all the loads - radio, lights, fridge etc. Without loads you will see what voltage and current are coming from controller. Or disconnect the loads on the battery, leaving just controller cables on. Post photo of the meter with toggle in "volts" and "amps".
Also, without loads (and without controller input) you will see if the battery is alive. For that, you have to disconnect everything from the battery and preferably give it 24 hours rest.