I have located a Service Manual for that model online:
http://techsupport.pdxrvwholesale.co...or-HE-0801.pdf
In reviewing the error code chart, there doesn't seem to be a condition where the all LEDs are on except the DC. Are the lights on steady, or flashing? Are you on shore power? Make sure your house battery is good, a bad battery can bring down the 12 volts and cause problems with electronic devices. Have you tried cycling the power?