This forum has been helpful so time to give back...
There is an undocumented (as far as I know!) error code involving the TEMPERATURE light on the Multiplus.
Normally, if the TEMPERATURE light is flashing, that means the internal MUTIPLUS circuitboard temperature is approaching its upper limit. This is documented in the manual. The light has an additional function that I have not seen documented anywhere.
When in CHARGE mode, if the battery temperature exceeds a preset limit (50C, I believe), the TEMPERATURE light flashes, and the charging current turns off when bulk phase completes and absorption phase of the charge cycle starts. (The part about the current shut down IS documented, but the flashing temperature light is not.)
If the TEMPERATURE light flashes while MAINS is on, and the inverter is off, try turning the MAINS power off. This shuts down the charger, and turns on the inverter. If the TEMPERATURE light immediately stops flashing, the problem is the battery temperature is too high. If the problem is truly the MULTIPLUS internal temperature, the temperature light will keep flashing.
