When a solar panel is wired to the solar input, no voltage output is measured on the battery leads. The Charge Controller is not damaged!
There is no voltage output because the Charge Controller requires the battery connection to function properly. Without a battery attached, the Charge Controller’s internal circuits cannot power up and allow current to flow from the Solar input to the battery.  You must connect battery to the charge controller first to allow it to properly bootup, and then solar can be applied.