Enphase
3T: Red 2 Flash

IQ Battery 3T Error State

IQ Battery 3T LED flashes red twice — battery in error. Wireless comms via COMMS-KIT-01 (Zigbee dongle).

COMMS-KIT-01 dongle removed from IQ Gateway USB port (most common silent failure)IQ Gateway offlineInternal PCU fault
STEP 1
FIRST CHECK: physically confirm the COMMS-KIT-01 Zigbee USB dongle is plugged into the IQ Gateway USB port. Removing this dongle is the most common cause of IQ Battery 3T communication and charging failure
STEP 2
If dongle is confirmed plugged in: cycle the battery DC switch (inside battery enclosure — requires removing quarter-turn thumbscrew cover). Wait 30s with switch off, then back on
COMMS-KIT-01 confirmed plugged in and DC switch cycled but error persists — PCU or hardware fault, escalate
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More Enphase fault codes

ACVOOR
AC Voltage Out of Range
ACFOOR
AC Frequency Out of Range
DC Res Low
DC Resistance Low (Ground Fault / GFDI)
DC Too Low
DC Input Voltage Too Low
DC Too High
DC Input Voltage Too High