IQ Battery 5P LED flashes yellow once per cycle — battery is not communicating with the IQ Gateway.
Common causes
IQ Gateway is offline or powered offComms Kit 2 (COMMS-KIT-02) USB cable not plugged into IQ GatewayWired control cable between Comms Kit and battery is disconnectedIQ Gateway firmware needs update
What to check
STEP 1
Check IQ Gateway is powered and shows solid green Network LED. Check Comms Kit 2 USB dongle is firmly plugged into IQ Gateway USB port
STEP 2
Trace the wired control cable from Comms Kit 2 to the battery control port. Cable must be fully seated at both ends. Power-cycle IQ Gateway (unplug from socket, wait 30s, reconnect)
Escalate if
Gateway is confirmed online, Comms Kit seated, control cables connected — fault persists for more than 20 minutes. Escalate to Enphase support
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