Solar Power Kit, no 5V output

Solar power kit (SKU-0210) outdoor 10W - Panel does not output +12V/5V even after connecting USBC connector to activate batteries.  My batteries are fully charged externally before installation.  My 5V load is 1mA, but there is no output.  I changed my load to 50mA but still there is no output.  While the USBC is connected it will output 5V ok. Why doesn't it output 12V/5V when power is supplied by the solar panel? The wiki contains no information on this.